Occult constipation in children: An unaddressed problem of our day-to-day practice

Abstract

BACKGROUND

In our day-to-day practice, constipation is a common problem in the pediatric population and cause of frequent visit in outpatient and emergency department. But occult constipation (OC) remains as the most unaddressed problem.

AIM

To investigate the clinical profile of OC in children.

METHODS

It was a prospective observational study, done in Bangladesh from January 2022 to December 2024. It included all consecutive children diagnosed as OC and were treated accordingly. Before diagnosis, secondary causes of the presenting symptoms were excluded with appropriate investigations. They were followed up monthly for 4 months and treatment response were measured by improvement of symptoms.

RESULTS

A total of 404 children were included in this study with mean age group of 76.50 ± 36.62 months, and male-female ratio of 1.67:1. The most common presenting complaint was abdominal pain (66%), followed by anorexia (49%), vomiting (24%), nausea (17%), frequent defecation with small volume stool (17%), altered bowel habit (16%), failure to thrive (14%) and recurrent helminthiasis (12%). Interestingly, 2.5% children presented with persistent diarrhea.

CONCLUSION

Abdominal pain is the most common presentation of OC. When symptoms cannot be explained by other etiology, OC should be kept in mind.

Key Words: Occult constipation; Children; Abdominal pain; Diarrhea; Recurrent helminthiasis

Core Tip: Occult constipation has a wide range of presentations, including abdominal pain, anorexia, vomiting, nausea, frequent defecation with small volume stool, altered bowel habit, failure to thrive, and recurrent helminthiasis. If we unable to address this condition, it will lead to unnecessary investigations and patients suffering.

INTRODUCTION

North American Society for Pediatric Gastroenterology, Hepatology, and Nutrition defined constipation as a delay or difficulty in defecation, present for 2 or more weeks and sufficient to cause significant distress to the patient[1]. It is a common problem in children, affecting 1%-30% (median 12%) of children worldwide[2]. Constipation accounts for 3% of all primary pediatric care visits and around 25% of pediatric gastroenterologist visits in the United States[3]. There is a common belief that constipation is not common in South Asian countries like Bangladesh, as the diet is rich in fiber here. There are hardly any studies related to constipation in developing countries, especially in South Asian countries[4]. A few recent studies showed that it is not uncommon in sub continental countries[5,6]. Benzamin et al[7] showed that 19% of school-aged Bangladeshi children had constipation. Constipation may be functional or due to organic causes. In another way, occult or overt constipation[8]. Occult constipation (OC) is a subtype of constipation, which can be defined as the absence of complaints of constipation on initial medical history or of symptoms to indicate the presence of constipation except for having hard consistency of stool in rectal examination or having fecal impaction in an abdominal X-ray[9]. As OC does not fulfill the definition of constipation, it remains unaddressed and undiagnosed. It has a variable presentation, and in the current literature review, there is a scarcity of data regarding OC. The present study has been undertaken to observe the clinical profile of OC among the Bangladeshi children.

MATERIALS AND METHODS

This prospective observational study was done at Department of Pediatrics, Sylhet MAG Osmani Medical College, and Dr. Benzamin’s Pediatric Liver Research Centre and Nutrition Clinic, Mount Adora Hospital, Sylhet, Bangladesh, from January 2022 to December 2024. All consecutive children (< 18 years), diagnosed with OC, were included in our study. OC was diagnosed based on negative history for constipation with fecal impaction on plain X-ray abdomen, which meets Leech criteria for OC (Figure 1). Each abdominal radiograph was divided into three colonic segments and fecal loading was evaluated as per Leech scoring system, where each score between 8 and 15, indicates significant constipation[10]. The sensitivity of Leech score in diagnosis of OC is significantly higher than any other scoring systems[11]. None of them fulfilled the Rome IV criteria for functional constipation and stool type on Bristol Stool Card was from type 3-7 (Bristol stool card was shown to parents/children to mark the stool pattern). The detailed clinical history, physical examination findings, and investigations done before visiting our center were recorded in a predesigned standard data sheet. During history taking, when the complaints of persistent diarrhea, encopresis, anorexia could not be explained by other conditions and needful investigations, then OC was considered. Physical examination of all samples was done by the researcher himself. The following data were obtained during physical examination: (1) Fever; (2) Mouth ulcer; (3) Abnormal thyroid gland; (4) Growth parameters; (5) Skin survey; (6) Per abdominal examination; (7) Tone/reflex of lower limb; (8) Spine of vertebra; (9) Abdominal distension; (10) Height and weight; and (11) Other red flag signs for constipation[12]. Every significant physical finding was recorded. The researcher did meticulous examination to rule out other possible pathologies. If any dilemma was present or not improved satisfactorily, re-examination and re-evaluation was done. Failure to thrive was defined as weight-for-height/length below the < 3^rd percentile on the National Center for Health Statistics growth chart. A secondary diagnosis was considered when patients failed to improve after adequate treatment. Weight gain crossing the 3^rd percentile of that baby after treatment is considered an improvement. When any red flag sings for constipation were present or patients failed to improve symptomatically, second diagnosis was considered. Investigations like complete blood count (CBC), serum glutamic pyruvic transaminase (SGPT), serum creatinine, urine routine and microscopic examination, culture and sensitivity, ultrasonography of the whole abdomen, Mantoux test, chest X-ray, endoscopy and colonoscopy, computed tomography (CT) abdomen, stool for Xpert MTB/RIF, celiac screening, etc., were done according to patient indications. Children who were diagnosed at presentation with overt constipation, co-morbid disease/chronic disease, on treatment for constipation, and poor drug compliance were excluded from the study. After the diagnosis of OC, treatment was initiated with magnesium hydroxide; for disimpaction 2 mL/kg/day followed by 1 mL/kg/day for 2 months for maintenance therapy and gradual tapering was done over one month. Patients were followed up monthly for 4 months. The treatment end points were improvement of symptoms, reported by caregiver or improvement of physical findings. Ethical clearance was taken from Departmental Review Board, Department of Pediatrics, Sylhet MAG Osmani Medical College Hospital, Sylhet. Informed written consent was taken from every participant's parent and confidentiality of data was strictly maintained.

Figure 1 Fecal impaction at caecum, sigmoid and rectum.

Statistical analysis

Statistical Package for the Social Sciences version 27 was used for data analysis. Symptoms were analyzed at the end of maintenance therapy for constipation, and treatment responses were compared before and after treatment of OC and estimated with the McNemar test, as variables of same subject was measured at two different points of time.

RESULTS

A total of 404 children were included in this study with mean age of 76.50 ± 36.62 months and male-female ratio of 1.67:1. All the children were on family food, and no gross feeding mismanagement was found. Sanitation and hygiene practices were good. Around 85% (343) of patients presented with several investigations like CBC, SGPT, serum creatinine, USG of the whole abdomen (80% of cases several times), amylase, lipase, etc., but only 3% (12) did a plain X-ray abdomen. During enrollment in this study, no definite secondary pathology or co-morbidity was present. The most common presenting complaint was abdominal pain (66%, 266), followed by anorexia (49%, 199), vomiting (24%, 97), nausea (17%, 69), frequent defecation with small volume stool (17%, 67), altered bowel habit (16%, 63), failure to thrive (14%, 57), recurrent helminthiasis (12%, 50), mucoid stool with straining during defecation (3%, 12), and encopresis (3%, 12). About 9% (36) of children had abdominal distention due to excessive colonic gas. Interestingly, 2.5% (10) children presented with persistent diarrhea, and 2% (8) children presented with repeated history of diarrhea. Palpable fecal mass was present in 7.92% (32) children, among them two patient was diagnosed as pelvic mass (both clinically and by USG), latter CT abdomen shows huge fecal impaction at rectum (Figure 2). Urinary complaints were also common, like increased frequency of micturition (7.5%, 30) and nocturnal enuresis (6%, 24). Other catchy points: 3% (13) children presented with unexplained excessive crying at night, which we diagnosed as pinworm infection with the presence of a worm on the rectum (Table 1). All the symptoms were significantly improved at the end of treatment and sustained during follow-up (Table 2). But few patients failed to improve after 2 months of treatment, and they were with chronic kidney disease (CKD) with obstructive uropathy (1, anorexia, nausea and occasional vomiting not improved), CKD due to tethered cord syndrome (1, urinary symptoms not improved), CKD (1, anorexia, nausea and occasional vomiting not improved), celiac disease (1, abdominal pain not improved), hypothyroidism (1, patient was overweight and abdominal distension not improved), intestinal tuberculosis (1, abdominal pain not improved), sacral meningocele (1, abdominal distension not improved), and lost to follow-up (4 cases).

Figure 2 Computed tomography scan of abdomen showing fecal mass at pelvis.

Table 1 Demographic characteristics and clinical features, n (%).

Features		Frequency, n = 404
Mean age (months), mean ± SD		76.50 ± 36.62
Male		253 (62.6)
Female		151 (37.4)
Male:female		1.67:1
Abdominal pain		266 (65.84)
Anorexia		199 (49.26)
Vomiting		97 (24.01)
Nausea		69 (17.08)
Frequent defecation		67 (16.58)
Altered bowel habit		63 (15.59)
Failure to thrive		57 (14.09)
Recurrent helminthiasis		50 (12.38)
Abdominal distension		36 (8.91)
Fecal mass on palpation		32 (7.92)
Itching anus		31 (7.67)
Increased frequency of micturition		30 (7.43)
Nocturnal enuresis		24 (5.94)
Excessive crying at night		13 (3.22)
Straining during defecation with mucoid stool		12 (2.97)
Encopresis		12 (2.97)
Persistent diarrhea		10 (2.47)
History of repeated diarrhea		8 (1.98)
Acute diarrhea		3 (0.74)
Per rectal bleeding due to solitary rectal ulcer syndrome		2 (0.50)
Prolapse		1 (0.25)

Table 2 Symptomatic response after treatment, n (%).

Complaints	At diagnosis	At the 4th month of follow-up
Abdominal pain	266 (100)	6 (2.25)a
Anorexia	199 (100)	10 (5)a
Vomiting	97 (100)	8 (8.25)a
Nausea	69 (100)	8 (11.60)a
Frequent defecation	67 (100)	0 (00)a
Altered bowel habit	63 (100)	1 (1.59)a
Failure to thrive	57 (100)	0 (00)a
Recurrent helminthiasis	50 (100)	2 (4)a
Abdominal distension	36 (100)	2 (5.56)a
Fecal mass	32 (100)	2 (6.25)a
Itching anus	31 (100)	0 (0)a
Increased micturition	30 (100)	2 (6.67)a
Nocturnal enuresis	24 (100)	3 (12.50)a
Excessive crying at night	13 (100)	0 (0)
Straining during defecation with mucoid stool	12 (100)	0 (0)
Encopresis	12 (100)	1 (8.33)
Persistent diarrhea	10 (100)	0 (0)1
History of repeated diarrhea	8 (100)	0 (0)1
Acute diarrhea	3 (100)	0 (0)1
Per Rectal bleeding due to Solitary rectal ulcer syndrome	2(100)	0 (0)
Prolapse	1 (100)	0 (0)

^aP < 0.001, McNemar Test.

¹Diarrhea improved and no further episode during follow-up period.

DISCUSSION

OC does not fulfill the definition and diagnostic criteria for constipation. That’s why it remains undiagnosed and unaddressed. Almost every patient has gone through several investigations before diagnosis, and symptoms persist unless the patient is treated for constipation. In our study, 85% of patients were referred, did several investigations, and received several symptomatic managements without improvement. This scenario was due to a lack of knowledge of the primary physician regarding the OC. Most common presenting features were abdominal pain (66%); among them, 95% were suffering from recurrent abdominal pain. Gijsbers et al[13,14] also found OC constipation as a cause of RAP in children (50%), who did not fulfill the Rome IV criteria for functional constipation and did not have any other organic disease. Borowitz and Sutphen[15] also state that 50% of OC presented with RAP. Vera Loening-Baucke and Swidsinski[16] found that constipation was the most common cause of acute abdominal pain in children. In our study, 3% of children were suffering from acute abdominal pain, requiring an emergency hospital visit. Raahave and Loud[17] found several symptoms like bloating (64%), abdominal pressure (60%), pain (26%), right iliac fossa tenderness (58%), fecal mass (42%), and meteorism (33%) in children with OC. In our study, we found 9% of children have abdominal distension, bloating, and fecal mass in 8%. Raahave and Loud[17] found hemorrhoids in 51%, but in our study, we had no such findings. Only 0.5% of the children had solitary rectal ulcer syndrome, according to our findings. Around 17% of children presented frequent defecation after meals. Stool was small volume with mucus, and along with abdominal pain (in 52 children), gives a diagnosis of diarrhea-predominant irritable bowel syndrome (IBS). However, based on the X-ray results, we identified the condition as OC and experienced a satisfactory recovery. This finding is similar to Tosto et al[18] who also described OC masked as IBS. In this study, we also found anorexia (49%), vomiting (24%), and nausea (17%) as presenting symptoms. Borowitz and Sutphen[15] in an OC study population found that 76% of children were suffering from recurrent vomiting, while other findings were symptoms of gastroesophageal reflux (50%) and nausea (18%). Anorexia is a common presentation of constipation, which potentially contributes to weight loss[7,19]. Constipation stimulated colonic mucin 2 secretion by activating NOD-like receptor family pyrin domain containing 6 inflammasome-mediated autophagy and modulated the composition of the mucosal microbiota and linked to functional dyspepsia[20]. In the present study, a history of repeated diarrhea (2%), persistent diarrhea (2.47%), and acute diarrhea (1%) were also presenting features. Borowitz and Sutphen[15] found that the number of children who experienced intermittent diarrhea was due to OC. Sayeed et al[21] showed that 11% of chronic diarrhea was due to constipation. This diarrhea, also known as paradoxical diarrhea or overflow diarrhea, occurs when liquid stool leaks around the hard impacted fecal matter in the rectum with frequent small watery bowel movements, occurring mostly involuntarily[22]. Among the persistent diarrhea cases, 3 children presented with ‘urine-like diarrhea (stool without fecal matter)’ (Video 1 and 2), which dramatically improved after disimpaction. This type of diarrhea is locally also known as ‘BB diarrhea/Bazlul-Benzamin diarrhea’. In these cases, all possible etiologies were excluded. When a large amount of hard, compressed fecal mass impacted at the level of the bowel that cannot be expelled spontaneously, resulting in colonic or rectal distention. Continuous contact between the feces and the colonic wall causes mucous membrane irritation resulting in profuse mucous secretion[23], which may cause profuse watery secretion. In this study, around 12% of children had a history of repeated Enterobius vermicularis (pinworm) infection, while 8% had a history of itching anus with occasional passage of worms, and 3% had excessive crying at night. The latter 2 symptoms were explained by pinworm infection. Perianal pruritus, which occurs primarily at nighttime while the affected individual sleeps, were the main presenting features of pinworm infection[24-26]. We found that 7% and 6% of children presented with urinary symptoms like increased frequency of micturition and nocturnal enuresis, respectively, which improved after treatment for constipation. Marks et al[27] showed that plain X-ray abdomen can be a sensitive tool in the diagnosis of OC as an etiology of lower urinary tract symptoms in children, where a history of constipation is absent. Choi et al[28] showed 82% of children with overactive bladder symptoms improve after laxative treatment. Maffei et al[29] found 37% of children with enuresis who had no history of constipation had OC. OC constipation is also a reversible cause of hydronephrosis[30]. In our study, mentioned symptoms were caused by fecal impaction, proven by improvement after treatment of constipation and no organic disease found except in a few cases. Raahave and Loud[17] also conclude like this, as attributed symptoms improved after a propulsive regimen. Hakimzadeh et al[31] showed poly ethylene glycol and lactulose were effective in treating abdominal pain in OC. But we used magnesium hydroxide/milk of magnesia, and we also found it effective in relieving symptoms of OC. Fecal loading causes various bowel symptoms and non-bowel symptoms. When no definite organic disease is found, a plain X-ray abdomen can give a diagnosis of OC[32], and laxative treatment may then improve these symptoms. This approach may prove cost-effective as an empirical interim measure, especially where healthcare resources are limited and where sophisticated imaging is not readily available. Choi et al[28] and Kang et al[33] also suggested a similar model of practice. OC diagnosis based on plain X-ray abdomen may miss the secondary pathology when the patient presented with abdominal pain and tenderness[34]. Another study by Freedman et al[35] showed that constipation diagnosis by plain X-ray abdomen may increase the risk of a revisit with a clinically important alternate-related diagnosis. In our study, we also found some organic disease during follow-up. On that point, we should always reconsider diagnosis if the patient presented with abdominal tenderness or failed to improve after disimpaction.

CONCLUSION

OC may often be under recognized in routine clinical practice and most commonly presented with abdominal pain, while anorexia, nausea, vomiting also common. Some atypical presentation also encounters in OC like frequent defecation, recurrent helminthiasis, increased frequency of micturition, nocturnal enuresis and diarrhea. If clinical features suggestive; before going any extensive investigation, we can consider plain X-ray abdomen for exclusion of OC, especially in resource constraints country. There were limitations of our study as sample size was small and done only in a specific region of Bangladesh.

ACKNOWLEDGEMENTS

All the children and their parents participating in this study.