[Predictive factors of severe Henoch-Schonlein nephritis in children: report of 34 cases]. / Les facteurs préédictifs des atteintes rénales sévères du purpura rhumatoïde chez l'enfant: a propos de 34 cas.

BACKGROUND: Henoch Schonlein Purpura is the most frequent vasculitis in children. Renal involvement is variable. Renal manifestations vary from isolated microscopic hematuria to the association on nephrotic syndrome to nephritic syndrome. AIM: To determine the predictors of severe Henoch - Schönlein nephritis. METHODS: Retrospective study over 15 years (1996-2010) of 34 chidren, with henoch-schonlein nephritis. RESULTS: Renal involvement was determined in 68.7%. Mean age was 7.23 years (3-14 years). Renal manifestations were variable. Moderate renal manifestations were noted in 15 cases. Microscopic hematuria was observed in 23.5% of cases and moderate proteinuria with or without hematuria is noted in 20.5% of cases. Severe nephritis was noted in 18 cases: nephrotic syndrome in 29.5 % and nephrotic syndrome associated to nephritic syndrome in 23.5%. Hypertension without urinary anomalies was observed in one case. In univariate analysis, factor predictive of severe nephritis were: male sex, macroscopic hematuria, biologic inflammatory syndrome and leukocytosis. In multivariate analysis, only the leukocytosis was predictor of severity. CONCLUSION: In our study, only leukocytosis was predictor of severity in henoch-schönlein nephritis.

Severe pneumococcal hemolytic uremic syndrome in an 8-month-old girl.

The hemolytic uremic syndrome (HUS), characterized by microangiopathic hemolytic anemia, thrombocytopenia and acute renal failure, represents one of the major causes of acute renal failure in infancy and childhood. The typical form occurring after an episode of diarrhea caused by Escherichia coli is the most frequent in children. Other microorganisms also may be responsible for HUS, such as Streptococcus pneumoniae, which causes more severe forms of the disease. We report an 8-month-old girl who presented with pneumonia and subsequently developed HUS. Renal biopsy showed characteristic lesion of thrombotic microangiopathy and extensive cortical necrosis. She was managed with peritoneal dialysis but did not improve and developed severe sepsis due to staphylococcal peritonitis, resulting in the death of the patient. Streptococcus pneumoniae-induced HUS is uncommon, but results in severe disease in the young. There is a high risk of these patients developing end-stage kidney disease in the long term.

Histopathological spectrum of childhood idiopathic steroid-resistant nephrotic syndrome in Tunisia.

BACKGROUND: In children, renal biopsy is routinely required in the management of idiopathic steroid-resistant nephrotic syndrome particularly prior to starting nephrotoxic immunosuppressive agents. AIM: To investigate the correlations between the results of initial renal biopsy in Tunisian children with idiopathic steroid-resistant nephrotic syndrome and the subsequent response to cyclosporineprednisolone combination. METHODS: We conducted a retrospective study of children with idiopathic steroid-resistant nephrotic syndrome over the period 2002- 2009. Data on clinico-biological features, histological diagnosis and response to cyclosporine-prednisolone were collected. RESULTS: Thirty patients were enrolled, of whom 16 had focal segmental glomerulosclerosis, eight had minimal change disease and six had diffuse mesangial proliferation. Complete Remission was achieved in 15 patients (50%). Nine patients (30%) went into partial remission. Only six patients presented no response (20%). No statistically significant relationship between the different pathological types and the response to CsA-prednisone was found. CONCLUSION: In our study, two important facts were noted: 1) the predominant histopathological subtype was the focal segmental glomerulosclerosis; 2) a high remission rate was achieved in our patients using a combined cyclosporine-prednisolone treatment regimen. This response is not dependent on the histological type.

[Interest of mycophenolate mofetil in children with membranous lupus nephritis]. / Place du mycophénolate mofétil dans la néphropathie lupique proliférative de l'enfant.

The management of lupus nephritis remains a clinical problem in children as in adults. Corticosteroids, cyclophosphamide and azathioprine have been used with satisfactory response, but the most important problems are their potential toxicities. Therefore, we evaluate the use of mycophenolate mofetil (MMF) as a new agent for treatment of lupus nephritis in children. Five children with biopsy-proven proliferative glomerulonephritis with active lesions received MMF, combined with corticosteroids during the induction phase and alone during the maintenance phase. We retrospectively studied the efficacy and safety of this therapeutic regimen. All patients had proteinuria and renal failure. Four patients from five presented nephrotic syndrome. During the induction phase, three patients achieved complete remission of their nephrotic syndrome with normalization of renal function. One patient achieved partial remission and kept moderate renal failure. One patient died at 50 days by severe sepsis secondary to leucopenia. During the maintenance phase, three patients had complete remission. One patient was kept proteinuria with a creatinine clearance of 55 mL/min/1,73 m². The growth of these patients is not affected. In childhood lupus proliferative glomerulonephritis, MMF was well tolerated, and most of the patients achieved remission and improvement of their renal functions.

Reversible nephrotic syndrome secondary to pulmonary hydatid disease.

Most patients with pulmonary hydatidosis are children. The disease may be asymptomatic or revealed by unusual events such as a glomerulopathy. An 8-year-old boy from a rural part of Tunisia presented with generalised oedema and macroscopic haematuria. There was no familial history of renal disease. He had a normal blood pressure (100/60 mmHg), and a pleural effusion was detected. Urinalysis showed nephrotic range proteinuria (375 mg/kg/d) and microscopic haematuria. His serum total protein concentration was 40 g/l and his serum albumin was 10 g/l. Renal biopsy showed capillary wall thickening and duplication, and mesangial cell proliferation in the glomeruli, characteristic of mesangiocapillary glomerulonephritis. Renal and abdominal ultrasound images showed increased echogenicity of the kidneys and mild ascites. Radiology revealed three large pulmonary hydatid cysts. The largest cyst occupied the entire right upper lobe and compressed the superior vena cava. Hydatid disease was confirmed by a strongly positive serum enzyme-linked immunosorbent assay (ELISA) for echinococcus. The patient was treated with high protein intake, dipyramidol and captopril; both right lung cysts were resected, followed by the left pulmonary cyst 4 weeks later. Hydatid cyst was confirmed histopathologically. He recovered well, the serum ELISA for echinococcus became negative, and follow-up urine examination and thoracic computerised tomography were normal 6 months after surgery, confirming good renal recovery and absence of pulmonary hydatid disease.

Role of genetic polymorphisms in factor H and MBL genes in Tunisian patients with immunoglobulin A nephropathy.

The molecular mechanisms of IgA nephropathy (IgAN) remain poorly understood. Several different polymorphic genes have been investigated in order to demonstrate their possible association with this disease. It is evident that mainly alternative and lectin pathways complement activation and play an important role in renal injury of IgAN. This study was conducted to determine eventual deficiencies of factor H in the SCR20 gene region and to look for a possible association between the polymorphism (+54) exon 1 of the MBL gene and the predisposition in Tunisian patients with IgAN. We then evaluated the effects of these FH mutations and/or this MBL polymorphism on nephropathy susceptibility and progression. Polymorphism A/B (+54) in the exon1 of the MBL gene and analysis within the C-terminal domain of the protein SCR20 in the exon 22 of the factor H (FH) gene were conducted in 36 sporadic IgAN Tunisian patients and 117 age and gender matched healthy subjects recruited from blood donors, by polymerase chain reaction-restriction fragment length polymorphism (PCR-RFLP) and direct sequencing respectively. The analysis of the Gly54Asp (+54) mutation of the MBL gene according to the criteria of gravity of the IgAN reveals that the patients with genotype AB present more frequently with end-stage renal disease (ESRD) compared with those of genotype AA [OR: 8, CI (1.74-54.49), P = 0.019]. Moreover, the variant allele B was statistically more frequent than the allele A in patients with an association with initial arterial high blood pressure, ESRD and class V of the Haas classification compared to those without this association (P = 0.009). The direct sequencing of exon 22 (SCR 20) of FH gene did not reveal any abnormal mutational deficiency for this factor in all patients and controls. The data did not support the hypothesis that FH is a susceptibility factor for the IgAN. However the data did show there was an association between AB (+54) exon1 MBL genotype and severe sporadic forms of this disease in Tunisian patients. Because of the small number of subjects studied, a much larger cohort of IgAN patients with varying severity of the disease and its progression would seem necessary to confirm these findings.

Tuberculosis in children undergoing hemodialysis.

UNLABELLED: Tuberculosis (TB) remains a public health problem in Tunisia. Its incidence is higher in immunocompromised hosts than in the general population. In children and during hemodialysis, TB is characterized by the frequency of extrapulmonary localizations and diagnostic difficulties. The aim of this retrospective study is to evaluate the incidence of TB in Tunisian children undergoing hemodialysis and to determine its clinical features as well as the results of chemotherapy. METHOD: This retrospective study includes seven TB children among 112 children on hemodialysis at the pediatric nephrology department in Charles Nicolle Hospital from 2002 to 2008. The diagnosis of TB was established by a combination of clinical, radiological, biochemical, microbiological, and histological examinations. Treatment with anti-TB drugs, the results of therapy, and the outcome of patients were noted. RESULTS: There were four girls and three boys aged 10 to 16 years (mean, 13 years). They had been on hemodialysis for 2 to 5 years (mean, 3 years). Noted clinical features were weight loss and fever in five cases, chest pain in one case, cervical lymph node in one case, and spinal pain in one case. The organ systems involved were pleural in two cases, pulmonary in one case, peritoneal in one case, cervical lymphatic in one case, and spinal in one case. One patient was treated empirically with a good response. Diagnosis was made by isolation of mycobacterium TB in three cases, by specific histological signs observed in a lymph node biopsy in one case, in peritoneal biopsy in one case, and in discovertebral biopsy in one case. In the remaining patient, the clinical and radiological presentations were compatible with pulmonary TB. All patients received four anti-TB drugs: isoniazid, rifampicin, pyrazinamide, and ethambutol. One patient died with miliary TB. The other patients had favorable outcomes. CONCLUSIONS: TB in hemodialysis children has a nonspecific clinical presentation. Extrapulmonary locations are most common. Diagnosis is often difficult, but successful outcomes are possible when made at an early stage.