Increased steroid responsiveness of young children with nephrotic syndrome in Nigeria

Childhood Nephrotic Syndrome in Africa: Epidemiology, Treatment Trends, and Outcomes

Nephrotic syndrome is a common childhood glomerular disease that is associated with massive proteinuria and edema. Children with nephrotic syndrome are at risk of chronic kidney disease, disease-related complications, and treatment-related complications. Patients with frequently relapsing disease or steroid toxicity may require newer immunosuppressive medications. However, access to these medications is limited in many African countries owing to prohibitive cost, the need for frequent therapeutic drug monitoring, and a lack of appropriate facilities. This narrative review examines the epidemiology of childhood nephrotic syndrome in Africa, including trends in treatment and patient outcomes. In most of North Africa, as well as among White and Indian populations in South Africa, the epidemiology and treatment of childhood nephrotic syndrome closely resembles that of European and North American populations. Historically, secondary causes of nephrotic syndrome (eg, quartan malaria nephropathy and hepatitis B-associated nephropathy) were predominant among Blacks in Africa. Over time, the proportion of secondary cases has decreased, along with rates of steroid resistance. However, focal segmental glomerulosclerosis increasingly has been reported among patients with steroid resistance. There is a need for consensus guidelines for the management of childhood nephrotic syndrome in Africa. Furthermore, establishing an African nephrotic syndrome registry could facilitate monitoring of disease and treatment trends, and provide opportunities for advocacy and research to improve patient outcomes.

Prospects of genetic testing for steroid-resistant nephrotic syndrome in Nigerian children: a narrative review of challenges and opportunities

The prevalence of childhood steroid-resistant nephrotic syndrome (SRNS) ranges from 35% to 92%. This steroid resistance among Nigerian children also reflects underlying renal histopathology, revealing a rare minimal-change disease and a varying burden of membranoproliferative glomerulonephritis and focal segmental glomerulosclerosis (FSGS). FSGS tends to progress to end-stage kidney disease, which requires dialysis and/or renal transplantation. While knowledge of the molecular basis of NS is evolving, recent data support the role of mutant genes that otherwise maintain the structural and functional composition of the glomerular filtration barrier to account for many monogenic forms of FSGS. With the advent of next-generation sequencing, >39 genes are currently associated with SRNS, and the number is likely to increase in the near future. Monogenic FSGS is primarily resistant to steroids, and this foreknowledge obviates the need for steroids, other immunosuppressive therapy, and renal biopsy. Therefore, a multidisciplinary collaboration among cell biologists, molecular physiologists, geneticists, and clinicians holds prospects of fine-tuning the management of SRNS caused by known mutant genes. This article describes the genetics of NS/SRNS in childhood and also gives a narrative review of the challenges and opportunities for molecular testing among children with SRNS in Nigeria. For these children to benefit from genetic diagnosis, Nigeria must aspire to have and develop the manpower and infrastructure required for medical genetics and genomic medicine, leveraging on her existing experiences in genomic medicine. Concerted efforts can be put in place to increase the number of enrollees in Nigeria’s National Health Insurance Scheme (NHIS). The scope of the NHIS can be expanded to cater for the expensive bill of genetic testing within or outside the structure of the National Renal Care Policy proposed by Nigerian nephrologists.

Childhood nephrotic syndrome at the University of Abuja Teaching Hospital, Abuja, Nigeria: a preliminary report supports high steroid responsiveness

The response to steroid in childhood nephrotic syndrome (CNS) varies across geographical regions, depending on aetiology, genetics, and the underlying pathology. Recently, there is an increasing steroid responsiveness among Nigerian children with nephrotic syndrome (NS). This is the first report of CNS at the University of Abuja Teaching Hospital, Gwagwalada, Abuja, Nigeria, between 15th January 2016 and 30th June 2018. Prednisolone was administered to all the children with NS according to the regimen of the International Study of Kidney Disease in Children. There were 46 children aged 17 months to 18 years, including 37 males and 9 females. The peak age was 6-10 years with a mean age of 8.2 ± 4.4 years. Forty-one (89.1%) had idiopathic NS (INS). Secondary NS occurred in five (10.9%) children with hepatitis B infection, sickle cell anaemia, haemolytic-uraemic syndrome, and post-infectious glomerulonephritis (two cases). Plasmodium malariae was not seen. Overall, steroid-sensitive NS (SSNS) was seen in 34 (73.9%) and in 32 (78%) with INS. Five (16.7%) of the 30 with SSNS relapsed on follow-up. Twelve (26.1%) were resistant to steroid (steroid-resistant NS, SRNS). Renal biopsies in five SRNS revealed focal segmental glomerulosclerosis in three, minimal change lesion in one, and severe interstitial fibrosis/glomerulosclerosis in another one. Four (8.7%) children who had SRNS died. A child with SRNS is surviving on renal transplant from a living-unrelated donor. The study supports the notion that steroid responsiveness is increasing among ethnic black Nigerian children. Pre-treatment renal biopsy may be unwarranted.

Childhood nephrotic syndrome in tropical Africa: then and now

This descriptive and comparative review examines the changing epidemiology, treatment, renal and patient outcome of childhood nephrotic syndrome (NS) in tropical Africa (TpAfr). In the 1960s to 1980s, corticosteroid-resistant non-minimal change disease (nMCD) including quartan malaria nephropathy (QMN) was the dominant renal histopathology type. The overall incidence of NS was 0.35-1.34% of hospital admissions. Median age at onset of NS ranged between 4.0 and 12.0 years while the mean (SD) age range was 5.8 (3.8) to 10.3 (4.8) years across studies. The male: female ratio was 1.6:1.0. The overall mean (SD) incidence of idiopathic minimal change disease (MCD) [21.6 (18.6%)] compared with idiopathic nMCD [59.1 (25.7%)] demonstrates significant dominance of the latter (p = 0.0001). Post-1989, the following mean (SD) incidences of histopathological types were: MCD 20.4 (17.7%), focal segmental glomerulosclerosis 39.0 (26.3%), membranoproliferative glomerulonephritis 25.4 (16.8%), proliferative glomerulonephritis 16.7 (27.0%) and membranous nephropathy 7.4 (4.5%). While the mean (SD) proportion of steroid resistance (SR) [73.5 (19.2%)] was significantly greater than the mean complete remission (CR) [26.5 (19.2%)] during 1960-1989 (p=0.005), mean (SD) SR [27.4 (25.3%)] was significantly lower than mean (SD) CR [66.1 (28.0%)] post-1989 (p < 0.001). Unlike QMN, hepatitis B virus, HIV infection, sickle cell disease and systemic lupus erythematosus are now increasingly being associated with NS in TpAfr. Mean (SD) renal survival post-1989 was 58.3 (37.0%) while all-cause mortality was 9.8%. Children with NS now survive better than before, reflecting improved access to healthcare and transition to a clinical pattern favouring idiopathic NS and increased sensitivity to corticosteroids.

Trends in the histopathology of childhood nephrotic syndrome in Ibadan Nigeria: preponderance of idiopathic focal segmental glomerulosclerosis

Background

Reports on the histopathology of childhood nephrotic syndrome (NS) had emanated from our Centre since the 1960s and by the late 1980s and early 1990s, a change was observed and reported. Taking into consideration the worldwide changing trend in the histopathology of the NS and our Unit policy change in the indications for renal biopsy, a change was envisaged. We therefore evaluated the current histologic pattern of childhood NS in Ibadan with the view to highlighting any variations from the past and comparing the findings with regional and global trends.

Methodology

We reviewed our database and analyzed the renal biopsy findings in patients who were biopsied before treatment was administered between 1997 and 2001 and those with mostly idiopathic steroid resistant NS (SRNS) and secondary NS, managed between 2006 and 2013. A comparative analysis of the findings from the present study was carried out with two previous reports from our Unit in the 1970s and early 1990s and also with reports from other Centres.

Results

A total of 78 patients had successful biopsies done during the study period in children aged between 2 ½ and 16 years. In both pre-treatment biopsy era (1997–2001) and post-treatment biopsy era (2006–2013), focal segmental glomerulosclerosis (FSGS) predominated. 75 % of the patients had idiopathic NS and among the patients that had idiopathic steroid resistant NS, FSGS was the most common followed by MPGN. For secondary NS, MCD was the most common but could be the early stages of either membranous nephropathy (MN) or FSGS. Chronic pyelonephritis and chronic interstitial nephritis occurred in 25 % of the study population but they were more prevalent in secondary nephrotic syndrome.

Conclusion

FSGS is the most common histopathology in children requiring renal biopsy in Ibadan presently. FSGS is also the most common histopathology in idiopathic SRNS, which is in keeping with reports from most parts of the world.

There has been a transition from the preponderance of Quartan Malarial Nephropathy (QMN) in the 1960s to MPGN in the 1980s to FSGS presently. This has great implications with regards to searching for new aetiologic factors, providing more efficacious treatment modalities and ensuring facilities for immunofluorescence, electron microscopic and genetic studies.

High Steroid Sensitivity among Children with Nephrotic Syndrome in Southwestern Nigeria

Recent reports from both Caucasian and black populations suggest changes in steroid responsiveness of childhood nephrotic syndrome. This study was therefore undertaken to determine the features and steroid sensitivity pattern of a cohort of black children with nephrotic syndrome. Records of children managed for nephrotic syndrome from January 2008 to April 2013 were reviewed. Details including age, response to treatment, and renal histology were analysed. There were 108 children (median age: 5.9 years, peak: 1-2 years), 90.2% of whom had idiopathic nephrotic syndrome. Steroid sensitivity was 82.8% among children with idiopathic nephrotic syndrome but 75.9% overall. Median time to remission was 7 days. Median age was significantly lower in steroid sensitive compared with resistant patients. The predominant histologic finding in resistant cases was focal segmental glomerulosclerosis (53.3%). No cases of quartan malaria nephropathy or hepatitis B virus nephropathy were diagnosed. Overall mortality was 6.5%. In conclusion, unusually high steroid sensitivity is reported among a cohort of black children. This is likely attributable to the lower age structure of our cohort as well as possible changing epidemiology of some other childhood diseases. Surveillance of the epidemiology of childhood nephrotic syndrome and corresponding modifications in practice are therefore recommended.

Clinical and laboratory findings and therapeutic responses in children with nephrotic syndrome

Nephrotic syndrome (NS) is a clinical entity characterized by massive loss of urinary protein leading to hypoproteinemia and edema. This prospective cross sectional study was performed on 44 children with idiopathic nephrotic syndrome (INS). The objectives were to study the clinical and biochemical parameters at the time of diagnosis of nephrotic syndrome and to study the histopathological distribution of different subtypes of INS and drug response pattern. There were 29 (66%) males and 15 females (34%). The mean age of NS was 4.87±3.24 years. Facial edema was found in 42 (95%), microscopic hematuria in 10 (23%), gross hematuria in 2 (4.5%), and hypertension in 5 (11.2%) of patients. In 17 children who underwent biopsy, focal segmental glomerulosclerosis was the most common pathologic finding (41%). Other subtypes included minimal change in three (18%), membranoproliferative glomerulonephritis in 1(5.8%), diffuse proliferative glomerulonephritis in 2 (11.6%), membranous glomerulonephritis in 1 (5.8%), and diffuse mesangial proliferation in 3 (17.5%) of cases. At the time of hospital admission, peritonitis were present in five (11.4%), pneumonia and upper respiratory infection (sinusitis) in eight (18%), cellulitis in two (4.5%). Among 44 children with NS, 29 (66%) were steroid sensitive cases, nine (20.5%) were steroid resistant and six (13.5%) were steroid dependent. Among patients with steroid sensitive NS, 37% were without relapsers, 38.8% frequent relapsers and 26.4% were infrequent relapsers. These results suggest that there are differences between season of incidence, response to treatment with corticosteroid and pathologic findings in our study and other studies in Iran and other countries.

Quartan malaria-associated childhood nephrotic syndrome: now a rare clinical entity in malaria endemic Nigeria

BACKGROUND

The study determined (i) whether or not quartan malaria nephropathy (QMN) is still a major cause of childhood nephrotic syndrome (CNS) in Nigeria, (ii) secondary causes other than QMN and their associated glomerular pathology and (iii) renal and patient outcome.

METHODS

The study was a prospective non-randomized study of consecutive cases of secondary CNS. Patients with idiopathic CNS were excluded.

RESULTS

Twenty-four of 78 (30.8%) CNS cases were of secondary aetiology. Overall mean ages at onset of secondary CNS aetiology and CNS onset were 8.97 +/- 3.59 (1-15.3) and 9.95 +/- 3.15 (5-15.3) years, respectively. Male (14)/female (10) ratio was 1.4. Secondary causes comprised systemic lupus erythematosus (SLE, 37.5%), sickle cell anaemia (SCA, 16.7%), hepatitis B virus (HBV, 16.7%) infection, Churg-Strauss syndrome (12.6%), SLE/human immunodeficiency virus infection (4.2%), rhabdomyosarcoma (4.2%), bee stings (4.2%) and Addison's disease (4.2%). The overall cumulative complete remission (CR) rate was 88.0%. Remission was sustained in 11 of 16 (68.8%) CR patients, while one patient (6.25%) relapsed; the remaining four patients (24.95%) were yet to attain sustained remission. Median relapse-free period was 10.5 (0.75-25) months. Cumulative renal survival was 75.2% at 3 years. Three patients were lost to follow-up, while two died. Overall cumulative patient survival probability at 36 months was 90.8%. All patients were followed for a median period of 12.5 (0.11-36.0) months.

CONCLUSION

Overall outcome of CNS has improved significantly compared to the 1960s and 1970s when the poor outcome of QMN was the predominant glomerular lesion in Nigeria. While quartan malaria-associated nephrotic syndrome has become a rare clinical entity, SLE, SCA and HBV infection have become the major secondary aetiologies of CNS in Nigeria.

Spectrum of childhood nephrotic syndrome in Iran: A single center study

Nephrotic syndrome (NS) is a clinical entity characterized by massive loss of urinary protein (primarily albuminuria) leading to hypoproteinemia (hypoalbuminemia) and its result, edema. Hyperlipidemia, hypercholesterolemia, and increased lipiduria are usually associated. Although not commonly thought of as part of the syndrome, hypertension, hematuria, and azotemia may be present. This prospective cross-sectional study was performed on 44 children (with age of onset up to 14 years) with idiopathic nephrotic syndrome (INS) in our center during 2000-2007. The objectives were to study the clinical and biochemical parameters and the histopathological distribution of different subtypes of INS and drug-response pattern in these patients. The study group included 44 children. There were 29 (66%) boys and 15 girls (34%). The mean age was 4.87 +/- 3.24 years. Facial edema was found in 42 (95%), microscopic hematuria in 10 (23%), gross hematuria in 2 (4.5%), and hypertension in 5 (11.2%) patients. In children who underwent biopsy, focal segmental glomerulosclerosis was the most common pathologic finding (41%). Other subtypes included minimal change disease in three (18%), membranoproliferative glomerulonephritis in one (5.8%), diffuse proliferative glomerulonephritis in two (11.6 %), membranous glomerulonephritis in one (5.8%), and diffuse mesangial proliferation in three (17.5%) cases. At the time of hospitalization peritonitis was present in five (11.4%), pneumonia and upper respiratory infection (sinusitis) in eight (18%), and cellulites in two (4.5%) patients. Twenty nine patients (66%) were steroid sensitive, 9 (20.5%) steroid resistant, and 6 (13.5%) steroid dependent. Among patients with steroid-sensitive NS, 37% were nonrelapsers, 38.8% frequent relapsers, and 26.4% were infrequent relapsers. Differences seems to exist between season of incidence, suitable response to treatment with corticosteroids, and pathologic findings of biopsy in our study and other studies from Iran and other countries.

Malaria-induced renal damage: facts and myths

Malaria infections repeatedly have been reported to induce nephrotic syndrome and acute renal failure. Questions have been raised whether the association of a nephrotic syndrome with quartan malaria was only coincidental, and whether the acute renal failure was a specific or unspecific consequence of Plasmodium falciparum infection. This review attempts to answer questions about "chronic quartan malaria nephropathy" and "acute falciparum malaria nephropathy". The literature review was performed on all publications on kidney involvement in human and experimental malarial infections accessible in PubMed or available at the library of the London School of Hygiene and Tropical Medicine. The association of a nephrotic syndrome with quartan malaria was mostly described before 1975 in children and rarely in adult patients living in areas endemic for Plasmodium malariae. The pooled data on malaria-induced acute renal failure included children and adults acquiring falciparum malaria in endemic areas either as natives or as travellers from non-tropical countries. Non-immunes (not living in endemic areas) had a higher risk of developing acute renal failure than semi-immunes (living in endemic areas). Children with cerebral malaria had a higher rate and more severe course of acute renal failure than children with mild malaria. Today, there is no evidence of a dominant role of steroid-resistant and chronic "malarial glomerulopathies" in children with a nephrotic syndrome in Africa. Acute renal failure was a frequent and serious complication of falciparum malaria in non-immune adults. However, recently it has been reported more often in semi-immune African children with associated morbidity and mortality.