Future of research on inflammatory bowel disease in Nigeria: Gaps and opportunities

Abstract

Inflammatory bowel disease (IBD) is an increasing global health issue that poses specific challenges in Nigeria. Although awareness of IBD is growing in the country, research and resources remain limited. This review aims to address this significant gap. To identify key gaps in IBD research within Nigeria and highlight opportunities for advancing future investigations to improve patient outcomes. A comprehensive review of the existing literature was conducted to evaluate current trends in IBD research, healthcare barriers, and potential areas for investigation specific to the Nigerian context. The analysis highlights significant deficiencies, including scarce epidemiological data, low levels of awareness among clinicians and patients, limited access to healthcare, and inadequate diagnostic and treatment resources. Additionally, there is a profound lack of localized research addressing genetic, environmental, and dietary factors relevant to the Nigerian population. Future investigations should prioritize epidemiological studies to assess IBD prevalence in Nigeria, establish specialized care centers for diagnosis and management, and launch public health initiatives to promote awareness and education. Strengthening collaboration between researchers, healthcare providers, and policymakers is imperative to achieving these goals. Bridging these research gaps presents an invaluable opportunity to enhance IBD healthcare delivery and patient outcomes in Nigeria. Collaborative, multidisciplinary efforts are essential for advancing knowledge, improving resources, and ultimately elevating the quality of life for individuals living with IBD in the country.

Key Words: Inflammatory bowel disease; Crohn's disease; Ulcerative colitis; Diagnostic challenges; Treatment accessibility; Public awareness; Clinician awareness; Inflammatory bowel disease registry; Research gaps; Multidisciplinary collaboration

Core Tip: To effectively tackle the increasing burden of inflammatory bowel disease (IBD) in Nigeria, a multifaceted approach is necessary. First, comprehensive epidemiological studies are vital to better understand IBD’s prevalence and risk factors. Raising public awareness through targeted education and improving healthcare professionals' knowledge with ongoing training are crucial for early detection. Enhancing healthcare infrastructure by establishing specialized IBD diagnostic and treatment centers is also essential. Finally, fostering collaboration among researchers, clinicians, policymakers, and patient advocacy groups will help advance research, streamline healthcare delivery, and improve patient outcomes.

INTRODUCTION

Inflammatory bowel disease (IBD) encompasses chronic, idiopathic inflammatory conditions affecting the gastrointestinal tract. The two primary forms of IBD are Crohn's disease (CD) and ulcerative colitis (UC), each distinguished by unique pathological features, disease distribution, and clinical manifestations[1-5]. While the precise etiology of IBD remains incompletely understood, it is widely accepted as a complex interplay between genetic susceptibility, environmental triggers, dysregulation of the intestinal microbiome, and aberrant immune responses in the gut mucosa[2,4-8].

EPIDEMIOLOGY OF IBD

IBD is an emerging global health issue marked by chronic gastrointestinal inflammation. While it is recognized as a pandemic disease, its prevalence and incidence vary significantly across different geographic regions and populations. The incidence and prevalence of IBD are continuing to rise worldwide, with an estimated 4.9 million cases globally reported in 2019, Wang et al[9]. The highest rates of IBD are generally observed in North America, Europe, and Australia. However, as suggested by the rise in incidence in newly industrialized regions, there is an incompletely understood role for environmental factors and lifestyle changes[1-3,10-14].

Global studies on IBD indicate a slight female predominance, typically ranging from 50% to 60%, Watermeyer et al[2]. In low-incidence regions, males are more commonly diagnosed with CD, while female predominance is more prevalent in moderate-to-high-incidence areas. Conversely, UC shows a slight male predominance in low and high-incidence regions, Ye et al[15].

IBD diagnoses usually follow a bimodal age distribution, with the first peak occurring in the second or third decade of life and a smaller second peak in the sixth or seventh decade. Although this bimodal distribution is often considered typical, CD more commonly exhibits a unimodal distribution, with a peak incidence in the second or third decade, Hodges et al[3].

Epidemiologically there is a shifting landscape as highlighted below

Global rise: The incidence and prevalence of IBD are increasing globally, especially in newly industrialized nations across Asia, South America, and the Middle East. The factors driving this are incompletely understood but westernized diet and altered gut microbiota are likely to play a role[16,17].

Geographic variation: Historically more prevalent in North America and Europe, IBD is now increasingly recognized in previously low-incidence regions. North America and Europe maintain the highest prevalence, while Asia is experiencing the most rapid increase in incidence. Some evidence suggests that the incidence in traditionally high-incidence regions are stabilizing, highlighting the dynamic nature of IBD epidemiology[16,18,19].

Childhood IBD is on the rise globally, with a significant number of diagnoses occurring before age 18. Early-onset IBD poses unique challenges, impacting growth, development, and psychosocial well-being[20-22].

Urban areas tend to have higher IBD incidence compared to rural areas, potentially due to differences in environmental exposures, dietary habits, and lifestyle[23-26].

IBD is observed at an intermediate rate among the white population in South Africa, it is less common among native Africans, with reports of IBD being rare in other African regions[2,3,27]. Historically, IBD has been considered uncommon in sub-Saharan Africa, including Nigeria. However, recent studies indicate a shift in this perception, showing an increasing recognition of IBD cases in Nigeria. A retrospective study across three tertiary centers in Southern Nigeria identified 12 IBD patients, with 66.7% diagnosed with UC and 33.3% with CD, Alatise et al[28]. Additionally, a study from Benin City reported 32 IBD cases over four years, Forae et al[29], and a more recent study revealed Nigeria had the third highest number of IBD cases in sub-Saharan Africa, with 25 cases from 8 centers recorded over two years, Hodges et al[27]. This upward trend aligns with broader regional patterns, suggesting that Western lifestyles and industrialization may contribute to the rising incidence of IBD, Hodges et al[3]. Common clinical manifestations in Nigeria include recurrent diarrhea, bloody stools, abdominal pain, and weight loss, with over 80% of patients presenting with moderate to severe disease, Hodges et al[27]. A case series further emphasized chronic bloody diarrhea, weight loss, and abdominal pain as key symptoms, highlighting the need for increased clinical awareness among healthcare providers, Alatise et al[28].

IBD AS A HEALTH CONCERN IN NIGERIA

While historically under-recognized, IBD is increasingly emerging as a significant health concern in Nigeria, demanding greater attention from healthcare providers, researchers, and policymakers[30,31]. The rising awareness and potential impact of IBD within the Nigerian healthcare landscape stem from a confluence of factors. These include growing interest among healthcare workers, rising prevalence of IBD, increased availability of endoscopy services, social media campaigns and lifestyle changes among others.

CHALLENGES IN DIAGNOSIS AND MANAGEMENT OF IBD IN NIGERIA

In Nigeria, patients frequently face significant delays in obtaining an accurate diagnosis of IBD due to the non-specific nature of symptoms such as abdominal pain, diarrhea, and weight loss. This, combined with a low index of suspicion for IBD, often results in misdiagnosis, with symptoms being attributed to more common conditions like infectious colitis or irritable bowel syndrome. Such misattributions can lead to inappropriate treatment and disease progression[3,29,30,32].

The diagnostic process is further complicated by Nigeria's high prevalence of infectious diseases that mimic IBD symptoms, including intestinal parasitic infections, typhoid fever, tuberculosis, and bacterial dysentery. Accurately distinguishing these conditions from IBD requires thorough stool studies and investigations for an appropriate diagnosis[3,30,32,33].

Moreover, access to specialized care poses significant challenges. Outside major urban centers, there is a notable shortage of trained gastroenterologists and dedicated IBD clinics, limiting access to advanced diagnostic and therapeutic options such as capsule endoscopy and biologic therapies. Many patients depend on general practitioners or primary healthcare facilities, where expertise in IBD management is often inadequate[3,30,32].

Financial constraints further exacerbate the problem, as the costs associated with endoscopic procedures, imaging studies, histopathology examinations, and essential medications—particularly immunomodulators and biologic agents—are often prohibitively expensive and typically not covered by health insurance. This economic burden restricts access to optimal care, leading to suboptimal treatment outcomes for many individuals with IBD[3,30].

IMPACT ON PUBLIC HEALTH AND SOCIOECONOMIC DEVELOPMENT OF IBD

IBD is a chronic and debilitating condition that significantly reduces the quality of life, functional capacity, and well-being of individuals. Persistent symptoms and complications—such as strictures and fistulas—often lead to physical disability, emotional distress, and social isolation, Buisson et al[34].

The strain on healthcare resources is substantial, resulting in undiagnosed or mismanaged IBD cases that increase resource utilization through frequent hospitalizations and long-term follow-ups, further burdening Nigeria's strained healthcare system. Economically, IBD imposes direct costs such as medical expenses and indirect costs from lost productivity, exacerbating poverty and hindering socioeconomic development, Ibukun et al[35].

THE OBJECTIVE OF THE REVIEW

In sub-Saharan Africa, particularly Nigeria, reports of IBD are significantly lower compared to Western countries, possibly due to underreporting, lack of awareness, and misdiagnosis. Most reported cases are in adults rather than children, and the established epidemiological risk factors for IBD in the West have not been thoroughly explored in the Nigerian population. This gap in understanding complicates the diagnosis and management of IBD, particularly due to limited diagnostic facilities and experienced healthcare personnel. Reduced access to effective medication and specialized care further exacerbates these challenges.

Thus, the objectives of this review are: (1) To examine current literature to highlight deficiencies in epidemiological data and knowledge of genetic, environmental, and dietary risk factors for IBD specific to Nigeria; (2) To explore potential areas for future studies, such as epidemiological research, establishment of specialized care centers, and public health initiatives focused on IBD awareness and education; and (3) To emphasize the need for collaboration among researchers, healthcare professionals, and policymakers to advance IBD research, enhance healthcare delivery, and improve patient outcomes in Nigeria.

METHODOLOGY

We reviewed studies on IBD in Nigeria from existing literature to identify gaps in existing research and propose actionable solutions. The review utilized academic databases such as PubMed, Google Scholar, and Scopus to gather relevant studies from peer-reviewed journals, conference proceedings, and grey literature. Due to the limited number of published studies relating to IBD in Nigeria, our review focuses on studies that provide epidemiological data, clinical characteristics, risk factors, healthcare access, diagnostic challenges, and patient management that are relevant to (rather than limited to) IBD within Nigeria.

A standardized form was developed to systematically capture key information from selected studies, including study design, sample size, demographics, diagnostic criteria, and reported cases. Analysis of the extracted data aimed to identify common trends and discrepancies, particularly focusing on gaps in epidemiological data, awareness of IBD among healthcare providers and the public, and the availability of resources for diagnosis and treatment. Identified gaps were categorized into the following thematic areas: Epidemiology; awareness; access; and resources.

Following this analysis, we developed targeted recommendations to address the identified gaps with a focus on priorities for future research, advancements in public and professional awareness, establishment of specialized IBD treatment centers, and enhancements in diagnostic resources. Proposed initiatives include the creation of a national IBD registry to improve data collection and investment in diagnostic capabilities. Finally, the findings were compiled into a comprehensive report, which will be disseminated through workshops, conferences, and publications to engage with stakeholders, aiming to advocate for necessary changes in IBD research and healthcare delivery in Nigeria.

THE EVOLVING LANDSCAPE OF IBD IN NIGERIA

IBD was historically considered rare in Nigeria and sub-Saharan Africa, but this perception is changing as the limited available evidence suggests an increasing incidence. Factors contributing to this shift include enhanced diagnostic capabilities and awareness among healthcare professionals, as well as changing lifestyles, diets and focus on infectious diseases. However, the true burden of IBD in Nigeria is likely underestimated due to persistent diagnostic challenges, such as limited access to diagnostic resources, the absence of a national registry, and issues of misdiagnosis and delayed presentation[27,28,36].

Emerging studies indicate that IBD diagnoses are on the rise, necessitating detailed characterization of the disease's phenotypic features in the Nigerian population. Barriers to effective management include significant diagnostic delays, a shortage of specialists, and the high cost of care, which restricts access to necessary treatments and diagnostic tools, such as colonoscopy. Moreover, treatment options are often limited to affordable medications, while biologics and other advanced therapies remain inaccessible to most patients. Addressing these challenges requires a multifaceted approach that includes improving data collection, increasing healthcare access, and enhancing patient education and support for those affected by IBD[27,37]. This trend aligns with patterns observed in newly industrialized countries experiencing epidemiological transitions. To grasp the effects of IBD in Nigeria, additional studies should be conducted across various medical centers.

OVERVIEW OF EXISTING IBD DATA IN NIGERIA AND IDENTIFIED DEFICIENCIES

A review of the literature on the epidemiology of IBD in Nigeria reveals numerous case reports and series but lacks analytic epidemiological studies to establish incidence or prevalence rates, see Table 1. These reports encompass both adult and pediatric cases[28-31,38-44] and highlight specific features such as perianal fistulating CD, Ajayi et al[45], and extraintestinal manifestations like pyoderma gangrenosum and pyostomatitis vegetans[38,46,47]. While most publications are from the 21st century, the earliest report dates back to 1970, Naish et al[47]. The largest case series, comprising 32 histologically confirmed cases over four years from January 2008 to December 2012, originates from a single center in Benin, with 43.8% diagnosed as CD, 37.5% as UC, and 18.7% as indeterminate colitis, Forae et al[29].

Pediatric IBD in Nigeria has primarily been reported from the southwestern region of the country, Adeniyi et al[31] documented eight cases, while Senbanjo et al[40] reported five cases in their studies conducted in the Lagos metropolis. Among the eight cases reported by Adeniyi et al[31], three were diagnosed with UC and two with CD; a similar distribution was noted by Senbanjo et al[40]. A small number of cases of very early onset IBD (VEO-IBD) were observed, with extraintestinal manifestations predominantly consisting of juvenile arthritis. Overall, there is a significant lack of reports from other regions of Nigeria.

The management of pediatric IBD in Nigeria faces several challenges, including the absence of diagnostic and therapeutic endoscopic facilities, a shortage of pediatric endoscopists and gastroenterologists, and the inaccessibility of therapies such as biologics for children with severe disease or VEO-IBD[31,40,48].

Several retrospective studies have examined colonoscopy findings across various centers, indicating differing rates of IBD detected during these procedures. In a 10-year review of colonoscopy records in Kano, suspected IBD lesions were the second most common finding after hemorrhoids, occurring in 18.1% of procedures, Musa et al[49]. Reports of colitis detected during colonoscopy at other centers range from 3.8% to 6.3%[50-52].

We recently published findings from a case reporting network across sub-Saharan Africa, which included eight respondents from various centers in Nigeria, Hodges et al[27]. Clinicians reported all new cases of IBD seen monthly over two years from August 2021 to August 2023. An initial reporting form asked physicians if they had encountered any new cases in the previous month, with a follow-up case reporting form generated for those who answered “Yes”, collecting basic demographic and disease data. During the study period, 25 cases were reported from Nigeria, with detailed demographic and disease information available for 14 cases. Among these, 10 were classified as UC (6 E2 and 4 E3 by Montreal classification), 3 as unclassified, and 1 as CD. The cohort comprised 10 males and 4 females, with a median diagnosis age of 36 years and a median time to diagnosis of 24 months (1 week to 96 months).

As part of this exercise, we attempted to estimate the incidence of IBD in regions reporting data from government centers with known catchment populations. The average number of cases per year was calculated using only the months when clinicians answered the initial “yes/no” questionnaire, instead of assuming that non-responses meant no cases were seen in that month. The estimated annual incidence in Sokoto, Nigeria, was 0.48 per 100000. This method has several limitations, including a less than 100% response rate from clinicians and the potential for other clinicians in the same catchment area, particularly in private healthcare institutions, to diagnose unreported cases. Despite limitations, it seems likely that Nigeria is in the early "emergence phase" of developing IBD, as outlined by Kaplan et al[53].

GLOBAL PERSPECTIVE ON IBD RESEARCH

IBD is increasingly recognized as a significant global health crisis, particularly in newly industrialized nations, necessitating research that reflects this growing burden[32,54]. Historically, IBD research has been dominated by Western perspectives focused on North America and Europe. To address variations in disease presentation and treatment responses, there is a crucial shift towards including diverse ethnic and geographic patient cohorts, particularly from Asia, South America, and the Middle East[55-57]. Current research emphasizes the interplay of genetic, environmental, and lifestyle factors, moving beyond a purely genetic perspective to consider the exposome's cumulative effects on IBD development[14,58].

Recent advances in IBD research highlight the importance of personalized medicine and patient-centered outcomes. This involves identifying biomarkers to tailor treatment strategies and incorporating patient-reported outcomes such as quality of life and psychological well-being into evaluations[59,60]. Key areas of investigation include the gut microbiome's role in disease pathogenesis, the modulation of immune cell activity, and the impacts of diet and nutrition on IBD symptoms and long-term outcomes[6,61]. Research funding is increasingly facilitated through government, industry, and non-profit organizations, though disparities exist based on geographical and economic factors. Global collaborations, including multinational trials and shared data platforms, are essential to advancing IBD research and improving care for affected populations[62-64].

OPPORTUNITIES FOR IBD RESEARCH IN NIGERIA

Future research should focus on epidemiological studies to determine the prevalence of IBD in Nigeria. Establishing specialized care centers will enhance research and improve patient access to treatment. Strengthening collaboration among researchers, healthcare professionals, and policymakers will further advance IBD research.

EPIDEMIOLOGICAL STUDIES

The data presented above highlight significant gaps in our understanding of the epidemiology of IBD in Nigeria, emphasizing the urgent need for population-based studies to assess the scale of the problem. Key requirements for such studies include a clearly defined catchment area with current population data, endoscopy, radiology, and pathology service, and a healthcare system encompassing primary and specialist services with an established referral process, Shivananda et al[65]. However, challenges such as the lack of population-level health data, poorly defined catchment areas, inadequate integration of private and public healthcare, and under-resourced public facilities complicate this effort. While hospital-based studies to determine IBD incidence, as previously described[66,67], may be feasible, they still face these limitations. Also, this method may not fully capture the large differences in incidence rates across different geographic areas. Possible approaches to epidemiological studies of IBD in Nigeria are discussed below.

The Global IBD Visualization of Epidemiology Studies in the 21^st Century (GIVES-21) study by Mak et al[68] was designed to investigate the incidence of IBD in newly industrialized countries across Asia, Africa (excluding Nigeria), and Latin America, employing a methodology similar to the Asia-Pacific Crohn’s and Colitis Epidemiology Study, Ng et al[69]. Both studies aimed to capture all new cases within well-defined study areas over a fixed period. In GIVES-21, all physicians—including gastroenterologists, family doctors, surgeons, and pathologists—within the study area were notified and encouraged to report every new case of IBD (patients presenting with persistent or relapsing diarrhea, blood and/or mucus in the stools for more than three weeks, or abdominal pain and weight loss). Similarly, endoscopy, radiology, and pathology records were reviewed for potential new cases during the study period.

This prospective method for determining incidence works best in isolated areas with stable populations and clear hospital catchment zones. It relies on collaboration between public and private healthcare sectors and requires educating stakeholders about IBD symptoms. However, it has limitations: It only identifies symptomatic IBD patients who seek medical attention, overlooking those who haven't sought help or who consult alternative sources like traditional healers.

An alternative method to assess prevalence and incidence was described by Sood et al[70] in the first population-based study of IBD in Punjab, North India, conducted over 20 years ago. Using a cluster sampling method, they performed house-to-house surveys in 226 clusters (total population: 51910) to identify potential cases (defined as anyone with a prolonged history of diarrhea, with or without rectal bleeding), then investigated through sigmoidoscopy and biopsy. Follow-up visits one year later identified new cases that developed symptoms during the interim, enabling incidence estimation. While this approach is relatively resource-intensive, it circumvents the underestimation of incidence and prevalence often seen in hospital-based studies.

In the first instance, we propose initiating a national registry for IBD cases in Nigeria, using a robust case definition to which hospitals and clinics could report new cases. This registry could strengthen epidemiological data, and provide valuable resources for researchers to explore various aspects of IBD. A network of hospitals, with at least one specialist gastroenterology clinic in each state reporting incident cases with basic demographic and disease details to a central secure database, would offer a comprehensive overview of IBD incidence in Nigeria and enhance collaboration among healthcare providers, researchers, and health policymakers.

GENETIC STUDIES

Genetic studies have significantly enhanced our understanding of the pathogenesis of IBD, with variants in NOD2 being the first linked to an increased risk of CD, Ogura et al[71]. Over the past 25 years, more than 300 risk loci associated with IBD have been identified, although these vary between populations. A genome-wide association study involving 2345 African American IBD patients identified African-specific risk loci for UC on LSAMP and ZNF649, genome-wide significant associations were not found for CD, Brant et al[72]. Most studies have focused on populations from regions with high IBD prevalence, such as Europe and North America. However, analyses of understudied populations have revealed variants significant for IBD treatment, such as the NUDT15 association with bone marrow toxicity and thiopurines, first identified in a Korean population, Yang et al[73].

It is crucial to include previously understudied populations, particularly those of African ancestry, in future genetic analyses of IBD. The African IBD Research Initiative, which encompasses several centers in Nigeria, aims to contribute to this effort by reporting data on the genetic determinants of IBD in sub-Saharan African populations, Croft et al[74].

ENVIRONMENTAL EXPOSURES

Populations with rapidly changing disease and exposure profiles are well-suited to identify relevant environmental triggers for IBD. The Environmental Triggers working group for the Crohn’s and Colitis Challenges 2024 Agenda emphasized the importance of examining environmental roles in "diverse populations that are understudied but are experiencing a rapid rise in disease incidence", Ananthakrishnan et al[75]. Nigeria may currently or soon fall into this category, presenting a unique opportunity to establish systems for studying environmental triggers.

Several environmental factors have been linked to IBD risk, including smoking, childhood antibiotic use, oral contraceptive use, appendectomy, breastfeeding, psychosocial stress, diet, and exercise, Kaplan et al[76]. However, the risk associated with these factors is not uniform across populations. For instance, a meta-analysis revealed that access to personal toilets and hot water significantly inversely correlated with UC only in non-white populations, Cholapranee et al[77]. While antibiotic use is a known risk factor for IBD in Western populations, Ungaro et al[78], it has been identified as a protective factor against IBD development in Asian populations, Ng et al[79].

Understanding the relationship between environmental factors and IBD development is crucial, as it may lead to preventive strategies, Lopes et al[80]. Therefore, this should be a priority area for IBD research in Nigeria.

DIET AND THE MICROBIOME

Certain diets have demonstrated therapeutic potential in CD, with the CD Exclusion Diet showing similar efficacy to exclusive enteral nutrition in an open-label randomized controlled trial, Levine et al[81]. Conversely, some diets may predispose individuals to IBD. The Prospective Urban Rural Epidemiology study, a cohort study involving participants from 21 countries, found an association between high intake of ultra-processed foods—such as soft drinks, refined sweets, salty snacks, and processed meats—and increased IBD risk, Narula et al[82]. In Nigeria, the nutrition transition has made these foods more accessible and frequently consumed, leading to a decline in consumption of indigenous, high-fiber traditional diets, Oyewole et al[83]. Elements of a more traditional Nigerian diet could potentially be protective against IBD, similar to protective effects observed with the Mediterranean diet[84,85].

There is preliminary evidence that a high-fiber, low-fat "African-style" diet can induce beneficial changes in inflammatory biomarkers among African Americans, O'Keefe et al[86]. Additionally, the relationship between diet and the microbiome is crucial. Urbanization and Western dietary habits have decreased beneficial bacteria like Prevotella while increasing mucin-degrading bacteria, such as Verrucomicrobia[87,88]. Lifestyle factors, including sibling multiplicity and animal ownership, are also linked to the preservation of a “non-industrialized-like” microbiome, Keohane et al[89]. This presents a research opportunity to explore dietary and microbiome shifts across Nigeria’s rural-urban spectrum and socioeconomic divisions to identify culturally appropriate interventions for treating or preventing IBD.

Future directions

Prospective population-based cohort studies in high-income settings have provided insights into the preclinical phase of IBD, such as identifying predictive biomarkers in the PREDICTS cohort in the United States, Torres et al[90], and increased intestinal permeability years before Crohn's diagnosis, associated with distinct microbiome and proteomic signatures in the CCC GEM cohort in Canada, Leibovitzh et al[91]. Applying this prospective cohort approach in regions where IBD is emerging may uncover important environmental and genetic risk factors, the effects of enteropathogen carriage, and the interplay among these elements in IBD development. Because IBD remains relatively rare in Nigeria, such studies would require collaboration between regional and international networks to achieve sufficient statistical power. Existing networks[27,74] should be leveraged for this purpose.

CONCLUSION

This review underscores the critical need to address gaps in research, healthcare infrastructure, and public awareness surrounding IBD in Nigeria. The lack of comprehensive epidemiological data significantly hinders our understanding of the true burden and risk factors associated with IBD within the Nigerian population. Limited awareness among clinicians and patients, combined with insufficient diagnostic and treatment resources, complicates the management of this complex disease. Without targeted efforts to overcome these barriers, IBD will continue to pose an unaddressed public health challenge in Nigeria (Table 1).

Table 1 Inflammatory bowel disease related studies conducted in Nigeria.

Ref.	Key objective	Study type	Regional location	Key findings
Alatise et al[28] (2012)	To present the experience of 3 tertiary health centres on IBD	Retrospective study	South-West	UC was reported in 66.7% of patients, with 33.3% diagnosed with CD. Severe disease was present in 83.3% of cases, and the primary clinical feature was muco-bloody diarrhoea
Forae et al[29] (2016)	Determine the frequency and morphological patterns of IBD in Benin City, Nigeria	Retrospective study	South-South	CD was observed in 43.8% of cases, UC in 37.5%, and IC in 18.7%. The male-to-female ratio was 1.9:1, with a mean age of 51.1 ± 7.2 years
Ekwunife et al[30] (2015)	Contribute to the growing literature on UC among Nigerians	Case series	South-East	Three cases of UC were reported: One patient underwent bowel resection due to massive gastrointestinal haemorrhage, while the others were diagnosed following colonoscopy and biopsy
Adeniyi et al[31] (2020)	Increase the awareness of this emerging condition in African children	Retrospective study	South-West	Eight children with IBD were evaluated, with a median age of 12.0 years. The most common presentation was chronic abdominal pain (50%). Two cases were CD, three were UC, and three were IC. Treatments included 5ASA, MTX, excusive enteral nutrition, and steroids
Ibukun et al[35] (2021)	The assessment focused on poverty levels among individuals with NCDs and the out-of-pocket expenses associated with these conditions	Cross sectional study	South-West	Twenty-five percent of respondents were multidimensionally poor, and 72% had no health insurance coverage
Kooffreh-Ada et al[39] (2024)	To share the experience of our gastroenterology practice in Calabar	Retrospective study	South-South	Eight patients presented with features consistent with IBD: Six had UC and two had CD. Seven patients had moderate disease, with recurrent mucoid bloody diarrhea as the main clinical feature. All cases were treated with 5ASA and AZA
Senbanjo et al[40] (2020)	The study highlights the occurrence, presentation, and management challenges associated with IBD	Case series	South-West	The median age was 9 years, with five cases identified. Three cases were diagnosed due to bloody diarrhea, while two were confirmed following surgical intervention for acute abdomen symptoms
Adepoju et al[41] (2021)	To demonstrate a rare concurrence of IBD and hemoglobinopathy	Case report	South-West	A 16-year-old girl was diagnosed with co-existing SCA and UC after presenting with a one-year history of recurrent peri-umbilical pain and bloody stools
Adeniyi et al[42] (2019)	CD has been reported to occur following therapy with etanercept in JIA patients	Case report		A 9-year-old with ileocecal disease CD was treated with steroids and sulfasalazine
Ukwenya et al[43] (2011)	Is IBD still a rare diagnosis?	Case series	North-West	3 cases of UC and one case of CD diagnosed in a tertiary institution
Senbanjo et al[44] (2012)	Reporting a case of ulcerative colitis in a 7-year-old girl	Case report	South-West	Left-sided colitis was confirmed by colonoscopy and biopsy in a patient who presented with frequent blood-stained stools, abdominal pain, and significant weight loss
Onyia et al[38] (2023)	Reporting a 40-year-old patient with UC who developed PG	Case report	South-East	A patient with UC diagnosed 20 years ago developed ulcers on the flexor surface of the right lower limb following trauma 10 years prior, diagnosed as PG. The patient was treated with infliximab and later mesalazine
Ajayi et al[45] (2010)	Reporting a case of CD presenting with a recurrent perianal fistula	Case report	South-West	A 23-year-old Asian male presented with recurrent abdominal pain, fever, arthralgia, perianal swelling, and a perianal fistula. Colonoscopy revealed CD affecting the entire colon. He was treated with corticosteroids and aminosalicylates
Alese et al[46] (2008)	Reporting on a 45-year-old man who presented with PG associated with UC	Case report	South-West	A 45-year-old man presented with rectal bleeding, lower abdominal pain, and superficial ulcerative lesions on the hand, neck, scalp, right gluteus, right inguinal area, and leg, confirmed as PG. He was treated with dapsone and prednisolone
Naish et al[47] (2015)	Reporting a rare occurrence of UC and pyostomatitis vegetans among the Nigerian population	Case report	South-West	A 26-year-old patient presented with bloody stools and oral rashes involving the mucosa of the cheeks, palate, buccal and vestibular surfaces of the gums, lateral margin of the tongue, and upper and lower lips. Sigmoidoscopy and biopsy revealed UC
Musa et al[49] (2021)	This study aimed to identify indications and colonoscopic findings among patients who underwent colonoscopy	Retrospective study	North-West	A total of 839 patient records were reviewed, with a mean age of 43.86 ± 18.36 years. The most common indication for the procedure was rectal bleeding (52.4%). The predominant finding was hemorrhoids (42.3%), followed by IBD lesions (18.1%)
Alatise et al[50] (2012)	This study aims to evaluate the demographic data of patients presenting for colonoscopy	Cross sectional study	South-West	In this study, 320 patients were recruited, with 56.9% being male and 43.1% female. The most common indications for colonoscopy were lower GI bleeding and changes in bowel habits (79.0%). The commonest endoscopic findings included hemorrhoids (20.6%, 66 cases), colorectal cancer (15.6%, 50 cases), polyps (10.3%), and IBD (3.8%)
Irowa et al[51] (2024)	This study aims to highlight the causes of hematochezia	Cross sectional study	South-South	Over a 9-year period, a total of 365 colonoscopies were performed. Hematochezia was the indication for 44% of these procedures. The causes of hematochezia included hemorrhoids (32.5%), colon cancer (23.8%), and inflammatory bowel disease (6.3%)
Akere et al[52](2016)	To evaluate the pattern of indications and spectrum of colonic disease at a tertiary healthcare facility	Cross sectional study	South-West	In this study, 250 patients were examined with male to female ratio of 1.1:1, mean age of 57.9 ± 14.2 years. Most common presentation was hematochezia (34.0%), the most common findings were colonic polyps (23.2%), and hemorrhoids (20.8%). IBD was seen in 4.0%
Oyewole et al[83] (2015)	To provide evidence-based information that will promote healthy lifestyle among urban dwellers	Systemic review	South-West	Industrialisation promotes creation of more job opportunities. However, many of the available workplaces in urban areas are not health-promoting because employees have poor access to preventive health information and sensitisation to healthy lifestyle has been poorly considered

IBD: Inflammatory bowel disease; UC: Ulcerative colitis; CD: Crohn's disease; 5ASA: 5-aminosalicylate; AZA: Azathioprine; SCA: Sickle cell anaemia; PG: Pyoderma gangrenosum.

To mitigate these challenges, the following recommendations are proposed

Establish a national IBD registry: Developing a centralized registry to systematically collect data on incidence, prevalence, and patient demographics will provide vital insights into the disease landscape and inform public health strategies.

Prioritize epidemiological research: Conducting studies on the genetic, dietary, and environmental factors specific to Nigeria will deepen understanding of IBD and support the development of tailored interventions. Collaboration with international researchers can also enhance methodological rigor and provide comparative insights.

Enhance diagnostic capabilities: Investing in advanced diagnostic tools, like colonoscopy facilities and trained staff, is essential for improving early and accurate diagnosis of IBD. Establishing specialized IBD care centers in underserved areas of Nigeria will enhance healthcare delivery even more.

Raise awareness and education: Public health campaigns targeting the general population and educational programs for healthcare providers are crucial to fostering a greater understanding of IBD. Building clinician knowledge will promote early recognition and better disease management, while public education will reduce stigma and empower patients to seek timely care.

Expand healthcare access: Improving healthcare infrastructure to ensure equitable access to diagnostic and treatment resources is essential. Subsidized care programs for economically disadvantaged patients and rural outreach initiatives can reduce disparities in care delivery.

Foster multidisciplinary collaboration: Encouraging partnerships between researchers, clinicians, policymakers, and patient advocacy groups will help drive progress in IBD research and healthcare delivery. Collaborative efforts should aim to secure funding, set research priorities, and advocate for policies that improve IBD care.

Support public health initiatives: Developing public health strategies that include community education, dietary guidance, and lifestyle interventions can address modifiable risk factors and improve overall disease outcomes.

Implementing these recommendations will help Nigeria reduce the future burden of IBD. A coordinated strategy that combines research, public awareness, improved healthcare access, and policy advocacy will enhance patient outcomes and strengthen the country's healthcare system for addressing chronic diseases.