Recurrent Urolithiasis Revealing Primary Hyperparathyroidism in a Nephrology Department.

Background: Urinary lithiasis constitutes a recurrent pathology affecting a relatively young population. The risk of progression to chronic renal failure and the cost of treatment are the most important issues. Primary hyperparathyroidism (PHPT) is responsible for urolithiasis and nephrocalcinosis in 7% of patients, and it represents the 7th cause of urolithiasis in Tunisia. Unfortunately, it remains an underdiagnosed pathology although it is curable. We aim to determine the clinical, biological, therapeutic, and evolutionary particularities of urinary lithiasis associated with PHPT in a nephrology setting. Methods: This is a monocentric, retrospective, descriptive study which took place in our nephrology department during the period from January 2010 to January 2023. Ten patients were included. All of them underwent blood and urine tests and a morphoconstitutional study of the urinary stones if possible. Results: The median age at diagnosis of PHPT was 42 years (34-54). The median time from the onset of kidney stones to the diagnosis of PHPT was 6.2 years (1-17). The male/female gender ratio was 0.66. Five patients had hypertension, two patients had obesity, one patient had diabetes, and three patients had urinary tract infections. Kidney stones were bilateral in eight cases and unilateral in two cases. Nine patients underwent urological intervention: surgery in 5 cases associated with nephrectomy in one case, extracorporeal lithotripsy in 4 cases, and percutaneous nephrolithotomy in two cases. The diagnosis of PHPT was retained with high or uncontrolled PTH associated with hypercalcemia in 8 cases and normocalcemic PHPT was found in 2 patients. Two patients had parathyroid adenoma and one patient had mediastinal adenoma. Radiology exploration was normal for the others patients. Surgery was performed in 7 patients and histology revealed an adenoma in 5 cases and hyperplasia in one case. The predominant urinary risk factors in our study were hypercalciuria in 6 cases and insufficient diuresis in 4 cases. Conclusion: This study underlines the role of the nephrologist in the exploration of urinary lithiasis and the prevention of recurrences, especially as PHPT is a curable aetiology of urolithiasis and affects a relatively young population. The determination of the epidemiological profile of patients with stones associated with primary PHPT and lithogenic risk factors allows the primary and secondary prevention of stone formation.

Primary Hyperoxaluria Type 1: Clinical, Paraclinical, and Evolutionary Aspects in Adults from One Nephrology Center.

Introduction: Primary hyperoxaluria type 1 (PH1) is a rare and inherited condition of urolithiasis. The aim of our study was to analyze clinical, paraclinical, and evolutionary aspects of PH1 in adult patients in our Nephrology department. Methods: We conducted a retrospective single-center study between 1990 and 2021. We collected patients followed for PH1 confirmed by genetic study and/or histopathological features of renal biopsy and morphoconstitutional analysis of the calculi. Results: There were 25 patients with a gender ratio of 1.78. The median age at onset of symptoms was 18 years. A delay in diagnosis more than 10 years was noted in 13 cases. The genetic study found the I244T mutation in 17 cases and 33-34 InsC in 4 cases. A kidney biopsy was performed in 5 cases, on a native kidney in 4 cases and on a graft biopsy in one case. The analysis of calculi was done in 10 cases showing type Ic in 2 cases. After a median follow-up of 13 years (1 year-42 years), 14 patients progressed to end-stage chronic renal failure (ESRD). The univariate study demonstrated a remarkable association with progression to ESRD in our population (44% vs. 56%) RR = 13.32 (adjusted ORs (95% CI): 2.82-62.79) (p < 0.01). Conclusion: Progression to ESRD was frequent in our series. Early diagnosis and adequate management can delay such an evolution.

Systemic lupus erythematosus presenting as lupus erythematosus tumidus and lupus nephritis: a case report.

BACKGROUND: Lupus nephritis and lupus erythematosus tumidus (LET) are uncommon manifestations of systemic lupus erythematosus (SLE), and their coexistence as the initial presentation of SLE is exceedingly rare. Here, we report such a case, emphasizing the diagnostic challenges and therapeutic implications of this unusual association. CASE REPORT: A 38-year-old North African woman presented in Nephrology department with a history of lower extremity edema, fatigue, and weight loss of 3 kg in 4 weeks. Physical examination revealed LET lesions on the chest and the Neck. Laboratory investigations showed lymphopenia, low C3 and C4 complement levels, positive antinuclear antibodies, anti-dsDNA antibodies, and anti-SSA/Ro antibodies. Renal function tests showed normal serum creatinine and nephrotic proteinuria. Renal biopsy revealed Class V lupus nephritis. Skin biopsy confirmed the diagnosis of LET, with the presence of lymphohistiocytic infiltrates and dermal mucin. The patient was diagnosed with SLE based on the 2019 EULAR/ACR criteria and treated with prednisone (1 mg/kg/day) and hydroxychloroquine. She showed significant improvement in her cutaneous and renal symptoms at 6 and 12 months follow-up. CONCLUSION: The rarity of the coexistence of LET and lupus nephritis as the initial manifestation of SLE, especially in the North African population, underscores the need for further research to elucidate the immunopathogenic mechanisms and prognostic factors associated with this association.

Multiple Myeloma in a Young Adult with Renal Involvement.

Multiple myeloma (MM) results from malignant plasma cell disorder. It represents approximately 10% of hematological malignancies and it is typically diagnosed in the elderly with a median age of 70 years and has a steep increase in incidence with advancing age. N Engl J Med. 2004, 1860; Clin Interv Aging. 2020, 619. The incidence of MM has been increasing over time, mostly due to population aging. Mayo Clin Proc. 2010, 225 However, certain MMs are diagnosed at young age even under 40 years old (2%). Leuk Lymphoma. 1998, 493; Blood. 2010, 5501. We report a case of a MM in a thirty-four-year-old woman whose circumstance of discovery was acute kidney failure.

Health related quality-of-life in systemic sarcoidosis in Tunisia.

INTRODUCTION: Sarcoidosis is a systemic granulomatosis that can be associated with large-scale physical and mental disability, affecting the health related quality-of-life (HRQoL) of patients. AIM: To evaluate the HRQoL of tunisian patients with sarcoidosis and to identify the factors that influence it. METHODS: We conducted an analytical, cross-sectional study collecting 31 patients with sarcoidosis according to the ATS/ERS/WASOG criteria. The evaluation of the HRQoL was assessed by two questionnaires in tunisian dialect. The generic score was the Medical Outcome Study 36-Short Form Health Survey (SF-36).The specific score used was the Sarcoidosis Health Questionnaire (SHQ). RESULTS: The HRQoL of our 31 patients was more affected in the three domains of the SHQ compared to the SF-36, which is in favor of the better sensitivity of the SHQ to detect the influence of the extent of sarcoidosis on the HRQoL. Factors associated with more impaired HRQoLwere: age at disease onset, age at interview, comorbidities, altered spirometry results, ocular involvement, chronic cholestasis, splenic nodules, arthralgia, organ count ≥3, lymphopenia and cholestasis at the time of the interview. Taking an immunosuppressant agent, particularly Methotrexate, was associated with HRQoL improvement. The number of relapses was the most correlated factor with an altered HRQoL, and this in several domains. CONCLUSION: For an effective management of patients with sarcoidosis, a bio-psycho-social approach is now necessary in order to assess the real and global impact of the disease and to improve the HRQoL of patients. Disease-specific scores seem more reliable in achieving these goals.

[Type IVa2 urinary lithiasis and associated pathologies: About 3 cases]. / Lithiase urinaire de type IVa2 et pathologies associées : à propos de 3 cas.

INTRODUCTION: Urinary lithiasis is a very common condition. The morpho-constitutional analysis of urinary stones is important for etiological diagnosis. It guides the explorations and the specific management. Type IVa2 stones are rare, have particular morphology and correspond to very targeted pathologies. We propose to report our cases of patients diagnosed with type IVa2 urinary lithiasis. METHODS: Our retrospective work focused on three cases of patients with the morphological type of renal lithiasis IVa2, collected between 2008 and 2020 in the Medicine A Department of Charles Nicolle Hospital in Tunis. RESULTS: All three patients were female; average age 37.6 years. The clinical symptomatology was identical marked by renal colic with recurrent episodes. The presence of a type IVa2 stone, isolated or associated with other components, guided the etiological investigation to look for a secondary or primary cause of distal renal tubular acidosis. We retained the diagnosis of a primary hyperparathyroidism in one case and a primary Gougerot-Sjögren's syndrome in the second case, and probable in the last case. CONCLUSION: Determination of urolithiasis nature (morphological and chemical), although carried out late, was of major interest to us and allowed us to make the diagnosis of distal tubular acidosis.

Thirty years of experience with anti-neutrophil cytoplasmic antibody glomerulonephritis in Charles Nicolle Hospital-Tunisia: a retrospective cohort study.

Introduction: antineutrophil cytoplasmic antibodies (ANCA) associated Glomerulonephritis (GN) is rare but a life-threatening disease especially, particularly in patients with advanced renal failure at presentation. This study aims to evaluate the epidemiological, clinical and histopathological features of renal involvement and investigate factors associated with ESRD. Methods: patients with renal biopsy-proven ANCA associated glomerulonephritis were included retrospectively over a thirty years period. The renal survival, defined as time to reach ESRD, was evaluated based on clinical parameters, histopathological classification as well as the renal risk score. Results: a total of 65 patients with crescentic GN were included in the study. The mean age was 47.9 years ± 22.4 years (range: 18-78) with an M/F sex ratio at 1.13. Hematuria, proteinuria and oliguria were found in respectively 100%, 81.5% and 56.2% of cases. Sixty patients (92.3%) had renal failure at presentation, and 30 patients (46%) required initial hemodialysis (HD) therapy. The pattern of glomerular injury was categorized as mixed in 43.7% of cases, sclerotic in 34.3%, crescentic in 16.6%, and focal class in 6%. Regarding renal risk score, patients were classified in the category low risk, intermediate risk and high risk with respectively 16.9%, 44.6% and 38.4%. All patients received corticosteroids and immunosuppressive treatment. Complete, partial remission and relapses were noted in respectively 15.3%, 18% and 72% of cases. Factors associated with ESRD were serum creatinine level >500 µmol/l (P=0,0016), CRP level >60 mg/l (P = 0,0013), interstitial fibrosis (P=0,0009) and glomerulosclerosis> 10% of total glomeruli (P=0,001). The survival rate was 89%, 60.9% and 32.8% at respectively 1, 5 and 10 years. Death occurred in 10 cases (15%) caused mostly by infections (40%). Initial serum creatinine level>140 µmol/l (P=0,02), alveolar hemorrhage (P=0.001) and infections (P=0,0001) were associated with mortality. Conclusion: in our cohort of ANCA GN, confirms the data showing improved patient survival but constantly high relapse risk. In addition, we observed that ANCA GN classification was predictive, as the risk of progressing to ESRD increased with the ascending category of focal, crescentic, mixed and sclerotic GN.

Renal Amyloidosis: Epidemiological, Clinical, and Laboratory Profile in Adults from One Nephrology Center.

Background: Renal amyloidosis is one of the main differential diagnoses of nephrotic proteinuria in adults and the elderly. The aim of this study with the most important series in our country is to contribute to the epidemiological, clinical, and etiological study of the renal amyloidosis. Methods: In a retrospective study carried out between 1975 and 2019, 310 cases of histologically proven and typed renal amyloidosis were selected for this study. Results: There were 209 men and 101 women with a mean age of 53.8 ± 15.4 years (range, 17-84 years). Of the 310 cases, 255 (82.3%) were diagnosed with AA renal amyloidosis and 55 (17.7%) with non-AA amyloidosis. Infections were the main cause of AA amyloidosis, and tuberculosis was the most frequent etiology. The period from the onset of the underlying disease to diagnosis of the renal amyloidosis was an average of 177 months. The most frequent manifestations at the time of diagnosis were nephrotic syndrome (84%), chronic renal failure (30.3%), and end-stage renal disease (37.8%). After a medium follow-up of 16 months (range, 0-68 months), mortality occurred in 60 cases. Conclusions: Given the high frequency of AA amyloidosis in our country, awareness of the proper management of infectious and chronic inflammatory diseases remains a priority in reducing the occurrence of this serious disease.

Overall of kidney transplant recipients with a pretransplantation cancer history.

No significant morbidity from recurrence cancer and no development of secondary type of cancers in pre-existing malignancies. We must be careful about risk of rejection.

[Emphysematous pyelonephritis and cystitis: An exceptional complication in a kidney transplant recipient]. / Pyélonéphrite et cystite emphysémateuses : une complication exceptionnelle chez un transplanté du rein.

Emphysematous pyelonephritis is a rare and severe infectious complication characterized by the presence of gas in the renal parenchyma, excretory cavities and surrounded tissues. It is due to the development of non-anaerobic gasifier bacteria. We report a new rare case of emphysematous pyelonephritis in a kidney transplant recipient, particular by its occurrence in a non-functional graft and its exceptional association with emphysematous cystitis.

[Successful treatment with paclitaxel of a visceral relapse of post-transplant Kaposi's sarcoma]. / Succès du traitement par paclitaxel d'une rechute viscérale d'un sarcome de Kaposi après transplantation rénale.

We report the observation of a patient who presented with post-transplant Kaposi's sarcoma after a delay of eight months with a dual cutaneous and palatal localisation. The reduction in immunosuppressive treatment and the introduction of Rapamune® allowed good clinical progress initially with regression of the skin lesions. He subsequently presented later a skin relapse with visceral localisation. Chemotherapy was conducted based on weekly paclitaxel infusions allowing partial remission and maintenance of renal graft function with good clinical tolerance.

Tubulointerstitial nephritis due to sarcoidosis: Clinical, laboratory, and histological features and outcome in a cohort of 24 patients.

Renal involvement is rare in systemic sarcoidosis. Among renal manifestations, tubulointerstitial nephritis (TIN) is the most commonly reported finding. We conducted the current study to investigate the clinical, laboratory, and histological features and to analyze the outcome of TIN due to sarcoidosis. We present a retrospective, single-center study of patients followed for sarcoidosis and presenting with TIN related to this systemic disease. Twenty-four patients were assessed (22 females/2 males). The mean age at diagnosis of TIN was 46.3 years. Extrarenal manifestations were dominated by thoracic involvement (95.8%), peripheral lymph nodes (54.2%), and skin lesions (33.3%). The mean proteinuria level was 0.68 g/24 h. Renal failure was diagnosed in 83.3% of cases with a median estimated glomerular filtration rate at 14.3 mL/min/1.73 m2. Nine patients presented with hypercalcemia and 12 patients with hypercalciuria. Renal biopsy was performed in 58.3% of cases. Six of the 14 patients presented with noncaseating granulomatous interstitial nephritis and eight with interstitial nephritis without granuloma. Granulomatous infiltration of renal parenchyma was complicated by vasculitis in two cases. Corticosteroid therapy was used in all patients. On follow-up analysis, four patients progressed to end-stage renal disease (ESRD) after a mean duration at 45.5 months. In the remaining patients, kidney function statistically significantly improved after one month of treatment compared to the time when the diagnosis was initially established (P = 0.031). We found that the predictive factors of progression to ESRD were multiorgan involvement (P = 0.032), advanced fibrosis F3 (P = 0.0006), and extensive interstitial granulomas (P = 0.007) and these were independently correlated with ESRD. Corticosteroid therapy seems to be effective in sarcoid TIN, but some degree of persistent renal failure is possible which can be predicted from both histologic findings and initial response to steroid therapy.

The role of IL-23/IL-17 axis in human kidney allograft rejection.

Th17 cell subset has been implicated in autoimmune diseases, tumor immunity and, transplant rejection. In order to investigate the role of IL-17/IL-23 pathway in allograft outcome, intragraft expression of IL-17 mRNA and single nucleotide polymorphisms (SNPs) of IL-17A, IL-17F, IL-17RC, and IL23R genes were evaluated with a quantification of IL-17A, IL-17F, and IL-23 plasma levels. This study revealed that recipients with acute rejection (AR) had a significant increase in IL-17A mRNA expression levels after transplantation compared to controls (P = 0.037). Moreover, IL-17A plasma levels were significantly higher in AR group; pretransplantation (Day-1 [D-1]): P = 0.00022 and posttransplantation (Day 7 [D7]): P < 10-14 . IL-17F and IL-23 plasma levels were significantly higher in AR at D7 only (47.86 vs. 22.99 pg/ml; and 33.82 vs. 18.811 pg/ml; P = 0.015 and P < 10-17 , respectively). Using receiver-operating characteristic curves, D7 IL-17A and IL-23 plasma levels exhibited excellent sensitivities and specificities for predicting AR. Genetic study revealed no association between IL-17A, IL-17F, IL-17RC, and IL23R studied SNPs and AR. Nevertheless, a significant improvement of graft survival was found in kidney transplant recipients carrying IL-17F-rs763780*A/A, IL-17RC*G/G, and *G/A genotypes. Besides, IL-17A mRNA levels were significantly higher in patients carrying the IL-23R*G/G genotype comparatively to those with *G/A genotype. Based on these findings, significant increase of IL-17A mRNA and protein levels in AR recipients that are genetically controlled highlights the role of this cytokine that can be a useful clinical biomarker to predict early acute renal allograft rejection.

Light chain nephropathy.

Light chain deposition disease (LCDD) is characterized by the tissue deposition of monotypic immunoglobulin light chains of either kappa or lambda isotype. It is the archetypal systemic disease that is most frequently diagnosed on a kidney biopsy, although the deposits may involve several other organs. This brief review focuses on the clinicopathological features of LCDD-associated nephropathy with an emphasis on the diagnostic and therapeutic difficulties related to this elusive condition.

First case of subcutaneous dermatomycoses in a Tunisian renal transplant patient.

BACKGROUND: Dermatophytes are keratinophilic and usually infect the corneal layer of the epidermis and appendages On the occasion of immunosuppression, such as solid organ transplant, they can invade deeper tissues or cause an infection of the skin and subcutaneous disseminated. AIM: To report the first observation of subcutaneous dematophytosis in a Tunisian renal transplant patient. CASE REPORT: A 29-year-old man had an erythematous lesion of 2 cm at the front of the left leg. He was treated with prednisone and tacrolimus. The skin lesion was has been neglected. The outcome was the occurrence of oozing whose mycological examination showed numerous hyphae and culture was positive for Microsporum canis. Initial treatment was voriconazole, but an interaction with tacrolimus has shortened the duration of treatment to 1 month. Three months later, the lesion became deeper, and then a biopsy was performed. The mycological examination showed the same appearance, previously described. The patient was put on fluconazole by adjusting the doses of tacrolimus and then underwent surgical excision of the lesions. The evolution after 4 months of antifungal treatment was favorable. CONCLUSION: The increasing incidence of immunosuppressive therapy has given rise to unusual clinical forms of invasive and sometimes serious fungal agents whose pathogenicity is usually limited. Clinicians should be mindful of superficial fungal infections of the skin in a renal transplant patient.

[Association of post-transplant lymphoproliferative disease and visceral leishmaniasis after kidney transplantation]. / Association d'un syndrome lymphoprolifératif et d'une leishmaniose viscérale après transplantation rénale.

Malignancies and opportunistic infections are frequently observed after solid-organ transplantation. Their occurrence strongly affects recipient survival. We report the case of a 29-year-old Tunisian kidney-recipient who was diagnosed simultaneously with post-transplant lymphoproliferative disease (PTLD) and visceral leishmaniasis (VL). Withdrawal of immunosuppressive therapy together with antiparasitic treatment using liposomal amphotericin B, and anti-CD20 antibodies medication resulted in cure of leishmaniasis and remission from PTLD. This case is of clinical interest because of the uncommon association of VL with PTLD after solid organ transplantation. It is also original by the favourable outcome of VL and PTLD, both known as life-threatening diseases. Also, it illustrates the predisposing role of immunosuppressive therapy in occurrence of opportunistic infections and malignancies after solid organ transplantation.

[Membranoproliferative glomerulonephritis in patients with cryoglobulinemia complicating hepatitis C virus: report of 11 cases]. / Glomérulonéphrite membranoproliférative secondaire à une cryoglobulinémie mixte compliquant une hépatite virale C: a propos de 11 cas.

BACKGROUND: Membranoproliferative glomerulonephritis in patients with cryoglobulinemia complicating hepatitis C virus have yet been reported. Although, it remains controversial, antiviral treatment seems to be able to improve the outcome of glomerulonephritis. AIM: The objectives of the study were to analyze characteristics of this association and to report literature data and newness treatment. METHODS: It's a retrospective study including 11 patients with membranoproliferative glomerulonephritis, hepatitis C virus and mixed cryoglobulinemia. Hepatitis C virus antibodies was identified by ELISA technique. Hepatitis C virus genotype was identified in one patient. Cryoglobulins were isolated from sera of all patients at 37 degrees Celsius. RESULTS: Patients were 3 men and 8 women with a mean age of 51.9 +/- 15.5 years. Between the 11 patients, 7 had hypertension, 9 had nephrotic syndrome and 10 had chronic renal failure. Renal biopsy showed membranoproliferative glomerulonephritis lesions in all cases with fibrinoid thrombi in 8 cases. Six patients had chronic liver disease. Liver biopsy was performed in 4 patients, showing histological feature compatible with chronic active hepatitis in 2 cases. No patient had antiviral therapy. Renal failure was stable in 5 cases and progressed in 6 cases with end stage renal failure in 3 of them. One patient died, 4 months after diagnosis, because of severe pulmonary involvement in cryoglobulinemic vasculitis. In literature, treatment is dominated by antiviral therapy composed first by Interferon Alpha alone. Combination therapy associating Interferon and Ribavirin was recently used in renal involvement; it is clearly more effective than interferon alpha alone. CONCLUSION: Hepatitis C virus detection should be performed when membranoproliferative glomerulonephritis is associated with cryoglobulinemia. Antiviral treatment should be more widely used in Tunisia to evaluate his effect on renal involvement

[Myeloma, Kaposi's sarcoma and HHV8 infection in hemodialyzed patient]. / Myelome multiple, maladie de Kaposi et infection par le HHV8 chez un hemodialyse chronique.

BACKGROUND: The association between Kaposi's sarcoma, Human Herpes Virus 8 infection and multiple myeloma is still controversial especially in hemodialysed patient. AIM: report a new case of this association. OBSERVATION: We report the case of a 83 year old man in whom the diagnosis of multiple myeloma of IgA/kappa had been made in December 2003 with end stage renal failure requiring hemodialysis. Initially, it had been treated with Melphalan, Cyclophosphamide, Prednisolone and Vincristine and secondary by Melphalan and Prednisone. Three months later, he had developed extensive porpour lesions in his lower limbs. Skin biopsy had been informed of Kaposi's sarcoma. Human Herpes Virus 8 test was positive. CONCLUSION: Our observation is another case supporting the hypothesis that Kaposi's sarcoma and multiple myeloma share a common aetiology such as Human Herpes Virus 8. The immunodepressed state related to aging, multiple myeloma, chemotherapy and hemodialysis was the probable factor responsible of rapidly progressive Kaposi's sarcoma in our patient. The association myeloma and Human Herpes Virus 8 infection is still controversial.

[Epidemiology of glomerular diseases in Tunisia from 1975 to 2005. Influence of changes in healthcare and society]. / Evolution du spectre des néphropathies glomérulaires en Tunisie de 1975 a 2005. Ses rapports avec l'évolution sanitaire et sociale.

Between April 1975 and March 2005, 4,436 cases of histologically proven glomerulonephritis (GN) were diagnosed by the same team at the Kidney Unit of Charles Nicolle Hospital in Tunis. Respectively 1,510, 1,419 and 1,509 cases were diagnosed in 1975-1985, 1985-1995, and 1995-2005. We compared trends in the incidence rates of the different types of GN and those of Tunisian indicators of health, social and economic status. The following differences were found between 1975-1985 and 1995-2005:--As a proportion of all cases of GN, the frequency of amyloidosis fell from 12,6 % to 6,5 % (p < 0,0001). The 444 cases of amyloidosis observed during the study period were of type AA in 87 % of cases, and were related to chronic infectious diseases in 239 cases (54 %; pulmonary tuberculosis in 114 cases). The frequency of tuberculosis-associated amyloidosis fell during the study period, in parallel with the reduction in the incidence of tuberculosis in the Tunisian population (48,7 cases/100,000 inhabitants in 1983 to 20,17 in 2004). Lupus nephritis accounted for 7.7 % of all cases of GN diagnosed in 1975-1985, compared to 13 % in 1995-2005 (p < 0,00001). Increased exposure to sunlight and use of cosmetics could be involved in this increase.--The incidence of both proliferative endocapillary and membranoproliferative GN (as a proportion of all cases of GN) fell between 1975-1985 and 1995-2005, from 15,9 % and 21,6 % to 6,9 % and 7,7 %, respectively (p < 0,0001). This matched a drop in the incidence of acute rheumatic fever in the Tunisian population, from 7,26/100,000 inhabitants in 1984 to 0,83 in 2004, probably as a result of public health measures and widespread use of antibiotics. The incidence of membranous GN increased from 11,1 to 17,7 % in adults (p < 0,001) whereas it fell from 10,1 to 4,6 % in children (p < 0,01), possibly as a result of a nationwide HBV vaccination program launched in 1995. The incidence of IgA nephropathy increased from 0,9 to 12,9 % in adults (p < 0,0001) and from 0,3 % to 18,4 % in children, but remained relatively stable in elderly adults. This study, conducted in a single center, by the same team, and using the same renal biopsy practices, confirms that the control of infectious diseases in Tunisia has led to a substantial regression of proliferative endocapillary and membranoproliferative GN and renal amyloidosis. Environmental factors, such as the adoption of western lifestyles, could explain the increase in lupus and IgA nephropathies.