Tuberculosis (TB) is still a health problem in developing countries. Pulmonary involvement remains the most common clinical presentation. However, multiorgan involvement can be life-threatening. We present the case of a young woman on peritoneal dialysis who was admitted to hospitalisation for hypercalcaemia and low back pain. In his biochemical evaluation, suppressed intact parthyroid hormone (iPTH) and elevated 1,25-hydroxyvitamin D were detected. On a lumbar CT scan, a hypodense lesion in vertebral bodies compatible with Pott's disease was found. Positive cultures for Mycobacterium bovis were obtained in bronchoalveolar lavage and peritoneal fluid, for which specific treatment was initiated. Due to neurological deterioration, a CT scan was performed showing the presence of multiple tuberculomas. Retrospectively, the lack of an etiological diagnosis of chronic kidney disease, the initiation of dialysis 8 months before and the clear evidence of long-standing TB strongly suggest mycobacterium infection as the cause or trigger for the rapid decline in kidney function.

People with Tuberculosis (TB) infection may present with glomerulonephritis (GN). The range of presentations, renal pathologies, and clinical outcomes are uncertain. Whether clinical features that establish if GN etiology is medication or TB related, and possible benefits of immunosuppression remain uncertain.

A scoping review was completed, searching MEDLINE, EMBASE, Cochrane Central Register of Controlled Trials, Web of Science and Conference Abstracts from Inception to December, 2023. The study population included patients with TB infection who developed GN and underwent renal biopsy. All data regarding presentation, patient characteristics, renal pathology, management of TB and GN, and outcomes were summarized.

There were 62 studies identified, with 130 patients. These cases included a spectrum of presentations including acute kidney injury, nephrotic syndrome and hypertension, and a range of 10 different renal pathology diagnoses. Cases that included immunosuppression and outcomes ranged from complete remission to long-term dialysis dependence. The presence of granulomas (4/4, 100%), anti-glomerular basement membrane disease (3/3, 100%), amyloidosis (75/76, 98.7%), and focal segmental glomerulosclerosis (2/2, 100%) were specific for GN being TB-infection related. On the other hand, minimal change disease was specific for anti-TB therapy related (7/7, 100%). While patients with more aggressive forms of GN commonly were prescribed immunosuppression, this study was unable to confirm efficacy. Only rifampin or isoniazid were implicated in drug-associated GN.

This study provides a clear rationale for renal biopsy in patients with TB and GN, and outlines predictors for the GN etiology. Thus, this study establishes key criteria to optimize diagnosis and management of patients with TB and GN.

Double-positive patients (DPP) exhibiting anti-glomerular basement membrane (GBM) and anti-neutrophil cytoplasmic antibodies (ANCAs) belong to an entity that is newly and poorly described, mainly in short series. We aimed to better characterize the epidemiological features, clinical presentation and therapeutic outcomes of these patients through a systematic review.

We performed a systematic review of English-, German-, Spanish- and French-written publications from February 1987 to March 2020 reporting cases of DPP using the following databases: PubMed, Scielo, ScienceDirect, Google Scholar, The Cochrane Library, Open Grey, The Grey Literature Report, Clinicaltrials.gov and International Clinical Trial Registry Platform of the World Health Organization.

In total, 538 DPP were identified from 90 articles. Their clinical presentations were often severe, and the majority exhibited acute kidney failure (91.8%) with a median initial serum creatinine level of 873 μmol/L; 50.7% had alveolar haemorrhage. Other manifestations were present in 30.3% of DPP, mainly ear, nose, throat and articular manifestations. ANCAs were predominantly directed against MPO (n = 377/523; 72.1%) compared to PR3 (n = 107/523; 20.5%), with rare cases of triple positivity (n = 15/538; 2.9%). Although most patients received initial immunosuppressive therapy (n = 285/317; 89.9%), the one-year overall, renal and relapse-free survival rates were 64.8%, 38.7% and 71.1%, respectively.

DPP are associated with the characteristics of two eponymous vasculitis types, responsible for a poor overall and renal prognosis. Thus, simultaneous testing of both antibodies and systematic renal biopsy should be recommended in every patient with rapidly progressive glomerulonephritis to recognize this difficult-to-treat and rare disease.

Atypical anti-glomerular basement membrane (GBM) disease, which is characterized by low levels of or negativity for anti-GBM antibodies in circulation but positivity in the kidney, has been recognized in this decade. However, a therapeutic strategy has not been established to date because its outcome is better than that of classic anti-GBM disease. This case report and literature review highlight atypical anti-GBM disease in infection-related rapidly progressive glomerulonephritis. A 72-year-old Japanese man diagnosed with methicillin-susceptible Staphylococcus aureus (MSSA)-induced vertebral osteomyelitis experienced for 2 months was referred to our hospital because of renal insufficiency. He developed rapidly progressive glomerulonephritis with a serum creatinine level of 6.8 mg/dL, C-reactive protein level of 9.7 mg/dL, urinary protein-to-creatinine ratio of 3.37 g/gCr, and gross hematuria. The serum anti-GBM antibody concentration was 3.5 U/mL, which was slightly above the normal range (< 3.0 U/mL). Conservative treatment, mainly with antibiotics, improved the symptoms and renal function. The serum anti-GBM antibody concentration peaked at 4.0 U/mL on day 7 and decreased to an undetectable range at the end of eight-week antibiotic therapy. This is the first case report describing the presentation and disappearance of serum anti-GBM antibody in a patient with MSSA infection. Conservative treatment may be effective for patients with atypical anti-GBM disease complicated by infectious diseases.

Antineutrophil cytoplasmic antibodies (ANCA) and Anti-glomerular basement membrane (GBM) antibodies often induce rapidly progressive glomerulonephritis (RPGN). Some reports have demonstrated RPGN with the sequential appearance of ANCA then anti-GBM antibodies, suggesting that ANCA may induce the development of anti-GBM antibodies. Whereas, many reports have shown that the development of ANCA is associated with various infectious diseases, such as non-tuberculous mycobacterial infection.

A 65-year-old woman with pulmonary non-tuberculous mycobacterial (NTM) infection was monitored without treatment. One year later, serum myeloperoxidase (MPO)- ANCA were elevated (14.1 U/mL (normal value < 3.0 U/ml)). A high fever and RPGN appeared 1 year later, and serum MPO-ANCAs were 94.1 U/mL. Anti-GBM antibodies were also detected. A renal biopsy revealed crescentic glomerulonephritis with linear deposits of IgG and C3c along the GBM and interstitial inflammation with endarteritis of arterioles. The diagnosis was RPGN associated with anti-GBM nephritis and ANCA-associated vasculitis.

This report shows that preceding NTM infection may have induced ANCA and anti-GBM antibodies and caused the development of RPGN.

As the population worldwide ages, the epidemic of kidney disease will also increase. Anti-neutrophil cytoplasmic antibodies (ANCA) positive rapidly progressive positive glomerulonephritis (RPGN) is the most common etiology for biopsied patients among the very elderly. Its pathological features and clinical course are well described, though there is still debate about the mechanism of injury involved in individual patients. From very ancient times, the cornerstone of treatment historically has been high-dose cyclophosphamide and a lengthy course of high-dose corticosteroids. Although this regimen has diminished the immediate mortality rate of RPGN, its intermediate and long-term adverse effects are not insignificant. Attempts to minimize toxicity and improve efficacy have been made through the years to allow physicians some options for therapy. Lower cumulative cyclophosphamide regimens, shorter corticosteroid courses, and the introduction of rituximab have modified the armamentarium for treatment of ANCA positive RPGN. As progress is made in understanding the molecular pathogenesis of this disease, new targets will be found for potential therapeutic attack. The complement system is an area of active interest for all glomerular diseases at this time. Indeed, animal studies and preliminary human studies suggest that targeting the complement system can ameliorate the course of ANCA-positive RPGN. Hopefully, as the population ages, we will see more and safer therapeutic options to treat this once rapidly fatal disease.

Coexistence of anti-glomerular basement membrane (anti-GBM) disease with anti-neutrophil cytoplasmic antibody (ANCA) is occasionally reported and termed "double positive" disease. Interestingly, the majority of "double positive" ANCA is myeloperoxidase (MPO)-ANCA, and some of the MPO-ANCA-positive cases reveal intrarenal arteritis indicating an ANCA-associated renal lesion. In contrast, proteinase 3 (PR3)-ANCA-positive "double positive" disease had rarely been reported, and as far as we know, none of the cases showed intrarenal arteritis. Herein, we report a case of PR3-ANCA-positive "double positive" anti-GBM disease presenting with pulmonary-renal syndrome and hemolytic uremic syndrome. The kidney biopsy showed crescentic glomerulonephritis, intrarenal arteritis, and thrombotic microangiopathy. This case newly describes PR3-ANCA-associated intrarenal arteritis in "double positive" anti-GBM disease.