RENAL DATA FROM THE ASIA - AFRICA
Year : 2010 | Volume
: 21 | Issue : 4 | Page : 778--783
Pattern of glomerular diseases in Sudanese children:A clinico-pathological study
Mohamed B Abdelraheem1, El-Tigani M.A Ali1, Reem M Mohamed1, Einas G Hassan1, Osman A Abdalla2, Salwa O Mekki3, BM Yousif3, Alan R Watson4,
1 Pediatric Nephrology Unit, Soba University Hospital, University of Khartoum, Sudan
2 Department of Radiology, Soba University Hospital, University of Khartoum, Sudan
3 Department of Pathology, Soba University Hospital, University of Khartoum, Sudan
4 Children's Renal and Urology Unit, Nottingham University Hospitals NHS Trust, QMC Campus, United Kingdom
Mohamed B Abdelraheem
Pediatric Nephrology Unit, Soba University Hospital, Khartoum
Glomerular diseases are a common cause of chronic kidney disease (CKD) in many countries. The pattern of glomerular diseases has been reported in adult Sudanese patients but there has been no previous study on Sudanese children. The aim of this study is to describe the pattern of glomerular diseases in Sudanese children from a clinico-pathological perspective. We retrospectively reviewed the clinical records of 321 children seen with nephritis/nephrosis at the Pediatric Nephrology Unit, Soba University Hospital and Dr. Salma Dialysis and Kidney Transplantation Centre, Khartoum, Sudan during the period from 2002 to 2007. Biopsies were studied with light microscopy and immunohistochemistry with electron microscopy performed abroad in selected patients (predominantly Alport«SQ»s). The mean age of the 321 study children was 8.71 years (range 2 months-16 yrs) of whom, 188 were males (60.2%). The most common presentation was with the nephrotic syndrome, seen in 202 patients (62.9%). The most common glomerular disease encountered was minimal change disease, seen in 96 children (29.9%), followed by post-infectious GN in 78 (24.3%) and focal and segmental glomerulosclerosis, seen in 44 patients (13.7%). Membranoproliferative GN (MPGN) was seen in 43 patients (13.4%) while mesangioproliferative GN was seen in 24 (7.5%). Systemic lupus erythematosus (SLE) was the most common secondary glomerular disease accounting for 16 patients (4.9%). HBsAg was positive in 10 patients and the most common associated lesion was MPGN (60%). Histopathology enabled us to change the therapy in 55.3% of the patients. Our study suggests that the pattern of GN in our cohort of patients is comparable with reports from other parts of the world with a high prevalence of post-infectious GN. Renal biopsies have an important part in planning therapy and management. Also, the importance of establishing a Sudanese renal registry including pediatric patients is stressed.
|How to cite this article:|
Abdelraheem MB, Ali ETM, Mohamed RM, Hassan EG, Abdalla OA, Mekki SO, Yousif B M, Watson AR. Pattern of glomerular diseases in Sudanese children:A clinico-pathological study.Saudi J Kidney Dis Transpl 2010;21:778-783
|How to cite this URL:|
Abdelraheem MB, Ali ETM, Mohamed RM, Hassan EG, Abdalla OA, Mekki SO, Yousif B M, Watson AR. Pattern of glomerular diseases in Sudanese children:A clinico-pathological study. Saudi J Kidney Dis Transpl [serial online] 2010 [cited 2022 Jun 25 ];21:778-783
Available from: https://www.sjkdt.org/text.asp?2010/21/4/778/64653
Glomerular diseases are the most common cause of chronic kidney disease (CKD) and/or end-stage renal disease (ESRD) in many countries. , In general, the incidence of CKD and renal failure is more common in developing countries than developed ones.  A recent survey about glomerulonephritis (GN) in developing countries showed that GN was the leading cause of CKD in 10% of patients in Egypt and Argentina, 20% in Thailand, South Africa and Venezuela and 40% in India and Pakistan.  A report from Nigerian children showed that GN was the cause of CKD in nearly half of their patients, while reports from the USA and Italy showed that GN was the cause of CKD in 10% and 6.8%, respectively. ,, Our previous report about the etiology of CRF in Sudanese children has shown that GN was the cause of CRF in 25%, while previous reports from adult Sudanese patients have shown similar prevalence of 33% and 38% as a cause of CRF. ,, However, comprehensive information about the etiology of CKD from developing countries is lacking due to the absence of renal registries.
The pattern of GN varies from country to country and it is believed that it is more common in tropical countries than developed countries and this is largely attributed to infections such as HCV and HBV, malaria, schistosomiasis, tuberculosis and malnutrition or genetic predisposition. However, a recent meta-analysis proved that there is no unique pattern of the underlying histological types of GN in African children. 
There are no previous studies about the pattern of GN in children in Sudan, although scanty data about adult GN has been reported. The aim of this study is to determine the pattern of GN in Sudanese children from a clinico-pathological perspective.
Material and Methods
Over a six-year period (2002-2007), we retrospectively reviewed the clinical and histological findings of 321 patients with different glomerular diseases at the Pediatric Nephrology Unit, Soba University Hospital and Dr. Salma Dialysis and Kidney Transplantation Centre, University of Khartoum.
The following clinical parameters were recorded: age, gender, mode of presentation, diagnosis, treatment and outcome. Laboratory parameters recorded included urine analysis, blood urea, serum creatinine, serum albumin and ASO titer and other serological tests, as required. Serum HBsAg, HCV and HIV were tested in all children with steroid dependent or steroid resistant nephritic syndrome or, when renal biopsy was indicated.
The demographics of the Khartoum state are composed of a cosmopolitan population representing the whole of Sudan. The total number of children received in our unit was from 16 states out of the 26 states of the country.
A total of 177 renal biopsies were performed. Indications for renal biopsy included: steroid resistant nephrotic syndrome (NS), steroid dependant NS and/or frequently relapsing NS in whom cytotoxic therapy was contemplated, renal failure of uncertain etiology, mixed nephriticnephrotic presentation, rapidly progressive GN and persistent or recurrent asymptomatic hematuria and/or proteinuria, patients with HBsAg positivity and SLE.
Percutaneous renal biopsy was obtained under ultrasound guidance after informed parental consent. Tru-cut needles were used in all cases and in the last two years, automatic needles were employed. The biopsy was considered adequate if it contained ten glomeruli or more. The sample for light microscopy study was fixed in 10% formaldehyde solution and the sections were stained by hematoxylin and eosin, periodic acid Schiff, silver methamine and in some cases masson trichome. Congo red stain was used when amyloidosis was suspected. Samples for immunohistochemistry were stained for IgG, IgM, IgA, C1q and C3. Electron microscopy study was performed in selected cases at laboratories in Germany.
During the period from 2002 to 2007, a total of 321 children with nephrosis and/or nephritis were retrospectively analyzed to study the pattern of GN. The mean age at the time of presentation was 8.7 years (range 2 months-16 years) and there were 188 male children (60.2%). The most common presentation was with the nephrotic syndrome, seen in 202 children (62.9%). The other 119 children presented with the nephritic syndrome and/or mixed features. The most common glomerular disease was minimal change disease seen in 96 patients (29.9%), followed by post-infectious GN in 78 (24.3%). A total of 177 renal biopsies were obtained; focal and segmental glomerulosclerosis was seen in 44 children (13.7%) and membranoproliferative GN was seen in 43 children (13.4%). The least common were Alport's syndrome, IgA nephropathy and membranous GN, which were seen in only 1.8%, 0.94%, and 0.3% of the patients, respectively. SLE was the most common secondary glomerular disease and accounted for 16 patients (4.9%) [Table 1].
Hepatitis B virus- associated glomerular diseases
Hepatitis B virus (HBV) infection was seen in ten children. The most common glomerular disease associated with HBV infection was MPGN, seen in six children (60%) followed by MsPGN in two children (20%). One child had FSGS associated with HBV and another had HBV and SLE. None of the children had infection with hepatitis C virus (HCV) or human immunodeficiency virus (HIV).
Familial glomerular diseases
Alport's syndrome was the most common familial GN seen in our children. Of the six children with Alport's syndrome, significant positive family history was elicited in four families. One family had three affected members (one died of ESRD, one developed CKD on followup and one had hematuria). Another family had one transplanted patient; two were on dialysis and one died. These families need further cytogenetic analysis, which is not available in Sudan. Another family with unspecified GN needs further genetic studies because of the possibility of hereditary nephritis.
Clinical course and outcome
Most children were on regular follow-up. A total of 158 (49.2%) improved and were discharged from follow-up, 113 (35.2%) remained on follow-up, 19 (5.9%) were lost to follow-up, 20 (6.2%) progressed to chronic renal failure and 11 (3.5%) died because of overwhelming sepsis, other complications or electrolyte abnormalities. All patients who were lost to followup were children from remote areas where there is lack of transport in addition to social and/or cultural beliefs or financial constraints. Of the 177 renal biopsies performed, a substantial change in the mode of therapy was seen in 98 children (55.3%) [Table 2].
To our knowledge, there is no populationbased epidemiological data on the spectrum of GN in Sudanese children. A review of GN will give us some insights into the spectrum of clinically significant renal diseases in the country. The prevalence of different histological types of GN in African children with NS has been reported earlier. There seems to be no unique pattern in Africa. In fact, the pattern varies according to the geographical area, environment and racial background. ,
Earlier large international series such as the international study of kidney diseases in children (ISKDC) have shown that MCD is the most common type of NS in children. A similar result is shown in our study. This pattern has been also reported from most of the other North African countries. , However, there are anecdotal reports from other parts of Africa; MCD was not the common pattern in Namibia (7.4%) and represented 27% of the cases in children in Senegal and 18% in Kenyan children. , This may be due to the fact that there is no renal registry in the majority of African countries and most children with MCD are seen in general pediatric clinics. Another fact is that we perform renal biopsy only selectively in the pediatric population and most other studies report mainly the histological types.
Unlike most reports from developed countries and neighboring countries, post-infectious GN was the second most common GN in our study, seen in 24.3% of the patients. It was secondary to streptococcal infection in the majority of children. Few children had HBV, malaria or schistosomiasis and in some children no cause could be identified. Renal biopsy is rarely indicated in this situation and the disease is usually self limited. However, many children were referred to our clinic because of the atypical presentation. Reports from Saudi Arabia showed a low prevalence of post-infectious GN of 4%.  Higher prevalence has been reported from other African countries. The spectrum of renal disease from East Nigeria showed 11.4% to have acute glomerulonephritis while previous reports from East Africa (where our study came from) showed even higher percentages of 30%. ,
Previous report of prevalence of FSGS in adult Sudanese patients in 1980 was 12%; this increased to 26.6% in 2004. , In our study, the prevalence of FSGS was 13.7%, similar to other reports from African countries; 14% from Senegal and 15% from Kenya, however, a lower prevalence of 6% from Zaire was also reported. ,, A higher frequency of 21% was reported from Indian South African children.  This difference may be due to geographical, racial, genetic and environmental factors.
The prevalence of proliferative GN, mainly MPGN and MsPGN, was 13.4% and 7.5% respectively; higher frequency has been reported from Kenya (25%), Zimbabwe (51%), and Cameron (24%). ,, However, similar results have been reported from Zaire (16%), and Senegal (10%). , This difference in prevalence and geographical pathology reflects the need for more collaborative studies between African countries.
The association of HBV infection and glomerular diseases has been described in different studies. Reports from South Africa showed that membranous nephropathy was associated with HBV infection in 40% of the black children. Similar results have also been reported in Namibian children. , The association with proliferative GN, FSGS and MCD has also been reported.  In our study, although HBV, HCV and HIV were performed routinely in the nephrotic children, only ten children were positive for HBV infection and the most common associated NS was MPGN seen in six children and MsPGN, seen in two children. This difference may be due to the lower prevalence of HBV in our community than other African countries.
Lupus nephritis was the commonest secondary GN in our study seen in 4.9% of the patients; it was also the commonest (11.6%) in a report published from adult Sudanese patients. 
The prevalence of IgA nephropathy from a previous adult Sudanese study was 4%.  In our study, lower prevalence was reported (0.9%), which was also shown in different African countries. However, this may not reflect the true prevalence of IgA in African countries because of the similar presentation of IgA nephropathy with post-infectious GN and the lack of immunoflourescence studies in most African countries.
The histopathological report helped us in changing the therapeutic decision by discontinuing or continuing steroids, or adding new immunosuppressive medications in 55.3% of the patients. Previous reports from adult patients have shown a change in therapy in 19 and 24% of the reported patients. , Another report from Chinese children showed a change in therapy in 25% while, a report from children in Singapore showed a change in therapeutic decision in 49% of the patients. ,
In our study, 50% of the children improved and were discharged from follow-up and another 50% either remained on follow-up (35%) (due to either hematuria and/or proteinuria or elevated BP) or were lost to follow-up (6%), developed CRF (6%) or died (4%). This data indicates clearly the severe pattern of GN in our cohort of patients and that it is one of the important causes of CRF in Sudanese children.
In conclusion, the pattern of GN in our cohort of patients is comparable with reports from other parts of the world with a high prevalence of post-infectious GN. Renal biopsies do have an important part in planning the management in our patients and the routine provision of EM is being developed. Our data further stresses the importance of establishing a Sudanese renal registry including pediatric patients.
|1||Anchoie I, Eke F. Chronic Renal Failure in Children: A report from Port Harcourt, Nigeria (1985 - - 2000). Pediatr Nephrol 2003;18:692-5.|
|2||Hattori S, Yosioka K, Honda M, Ito H; Japanese Society for Pediatric Nephrology. The 1998 report of the Japanese National Registry data on Pediatric end-stage renal disease patients. Pediatr Nephrol 2002;17:456-61.|
|3||Barsoum RS. Overview: End-stage renal disease in developing world. Artif Organs 2002;26(9): 737-46.|
|4||North American Pediatric Renal Transplant Cooperative Study (NAPRTCS). 2005 annual report. The EMMES Corporation, Rockville, MD; 2005.|
|5||Ardissino G, Dacco V, Testa S, et al. Epidemiology of chronic renal failure in children: data from the Italkid project. Pediatrics 2003; 111:e382-7.|
|6||Ali E, Abdelraheem M, Mohamed R, Hassan E, Watson AR. Chronic renal failure in Sudanese children: Aetiology and outcomes. Pediatr Nephrol 2009;24(2):349-53.|
|7||Osman EM, Abboud OI, Danielson BG. Chronic renal failure in Khartoum, Sudan. Upsala J Med Sci 1987;92:65-73.|
|8||Abboud OI, Osman EM, Musa AR. The aetiology of chronic renal failure in adult Sudanese patients. Ann Trop Med Parasitol 1989;83(4): 411-4.|
|9||Ehrich JH, Eke FU. Malaria induced renal damage: Facts and myths. Pediatr Nephrol 2007;22:626-30.|
|10||Doe JY, Funk M, Mengel M, Doehring E, Ehrich JH. Nephrotic Syndrome in African children: lack of evidence for tropical nephrotic syndrome? Nephrol Dial Transplant 2006;21: 672-6.|
|11||Nephrotic syndrome in children: prediction of histopathology from clinical and laboratory characteristics at time of diagnosis. A report of the International Study of Kidney Disease in Children. Kidney Int 1978;13:159.|
|12||Verroust P, Ben-Maiz H, Morel-Maroger L, et al. A clinical and immunological study of 304 cases of glomerulonephritis in Tunisia. Eur J Clin Invest 1979;9:75-9.|
|13||van Buuren AJ, Bates WD, Muller N. Nephrotic syndrome in Namibian children. SAMJ 1999;89 (10):1088-91.|
|14||Satge P, Habib R, Quenum C, Boisson ME, Niang I. Pattern of Nephrotic syndrome in Children in Senegal. Ann Pediat 1970; 17:382-93.|
|15||McLigeyo SO. Glomerular diseases in Kenya - another look at diseases characterized by nephrotic proteinuria. Afr J Health Sci 1994;1:185-90.|
|16||Essam A. Spectrum of glomerular diseases among children in Saudi Arabia. Saudi J Kidney Dis Transpl 1997;8(3):285.|
|17||Eke FU, Eke NN. Renal disorders in children: a Nigerian study. Pediatr Nephrol 1994;8:383-6.|
|18||Musa AR, Veress B, Kordofani AM, Asha HA, Satir A, El-Hassan AM. Pattern of the nephrotic syndrome in the Sudan. Ann Trop Med Parasitol 1980;74:37-44.|
|19||Eman HK, Kaballo BG, Suleiman SM, Khalil EA, El-Hassan AM. Pattern of glomerulonephritis in Sudan: Histopathological and Immunofluorescence study. Saudi J Kidney Dis Transpl 2004; 15(2):176-9.|
|20||Pakasa M, Kalengayi MR. Nephrotic syndrome in Zaire: Morphological and aetiological aspects. Trop Med Parasitol 1984;35:193-5.|
|21||Bhimma R, Hoosen M, Coovadia, Miriam Adhikai. Nephrotic syndrome in South African children: changing perspective over 20 years. Pediatr Nephrol 1997;11:429-34.|
|22||Seggie J, Davies PG, Ninin D, Henry J. Pattern of glomerulonephritis in Zimbabwe: Survey of disease characterized by nephrotic proteinuria. Quarterly J Med 1984;209:109-18.|
|23||Mbakop A, Youmbissi TJ, Gonsu JD, Chatelanat F, Ngu JL. Renal puncture biopsy in nephrotic syndrome in Cameroonian children, adolescents and adults: histopathologic profile according to age. Arch Anat Cytol Pathol 1990; 38:104-7.|
|24||Parone DB, Meyer LE. The effect of biopsy on therapy in renal disease. Arch Intern Med 1981; 141:1039-41.|
|25||Reddy J, Lynn KL, Baily RR. Renal biopsy: An appraisal of its role in clinical nephrology. N Z Med J 1981;94:96-8.|
|26||Lai KN, Lai FM, Chan KW, Au TC, Tam A, Leung NK. Pattern of glomerulonephritis in Chinese populations: the effect of renal biopsy on therapeutic decision. Aust Paediatr J 1987; 23:231-4.|
|27||Yap HK, Murugasu B, Saw AH, et al. Pattern of glomerulonephritis in Singapore Children - A renal biopsy perspective. Ann Acad Med 1989; 18(1):35-9.|