Nephrotic syndrome in the elderly: epidemiological aspects, clinical data, and renal biopsy findings

Nephrotic syndrome is the most common clinical presentation of glomerular disease in elderly patients, and renal biopsy is an important diagnostic resource. The aim of this study was to describe nephrotic syndrome among elderly patients in Brazil, focusing on tubulointerstitial and vascular involvement. This was a retrospective study of patients over 65 years of age with nephrotic syndrome who underwent renal biopsy between January 2012 and December 2019. Of the 123 renal biopsies that occurred during the study period, 44 (35.8%) were performed for the investigation of nephrotic syndrome. Among those 44 cases, the main etiologies were membranous nephropathy in 13 cases (29.5%), amyloidosis in ten (22.7%), non-collapsing focal segmental glomerulosclerosis (FSGS) in four (9.1%), and collapsing FSGS in four (9.1%). Patients with minimal change disease (MCD) had the lowest degree of interstitial fibrosis compared with the other glomerulopathies, and histological signs of acute tubular necrosis (ATN) were less common among those with amyloidosis than among those with membranous nephropathy, FSGS, or MCD (P=0.0077). Of the patients with ATN, the frequency of acute kidney injury (AKI) was highest in those with MCD (P<0.001). All patients had some degree of vascular involvement, regardless of the type of glomerulopathy. In conclusion, the second most common cause of nephrotic syndrome in this population was amyloidosis, and acute interstitial tubule involvement was more marked in MCD. Vascular involvement is something that cannot be dissociated from the age of the patient and is not only due to the underlying glomerulopathy.

Dialysis-related constrictive pericarditis: old enemies may sometimes come back

Cardiovascular disease is the main cause of death in patients with chronic kidney disease (CKD). Several heart conditions have been associated with CKD, including myocardial and pericardial diseases. This paper describes a case of Dialysis-related constrictive pericarditis in a patient diagnosed with sudden hypotension during a hemodialysis session. A 65-year-old man diagnosed with hypertension, diabetes, obesity, and cirrhosis on hemodialysis for two years complained of symptoms during one of his sessions described as malaise, lipothymia, and confusion. The patient had a record of poor compliance with the prescribed diet and missed dialysis sessions. He was sluggish during the physical examination, and presented hypophonetic heart sounds, a blood pressure of 50/30mmHg, and a prolonged capillary refill time. The patient was referred to the intensive care unit and was started on antibiotics and vasoactive drugs. His workup did not show signs of infection, while electrocardiography showed low QRS-wave voltage. His echocardiogram showed signs consistent with a thickened pericardium without pericardial effusion. Cardiac catheterization showed equalization of diastolic pressures in all heart chambers indicative of constrictive pericarditis. The patient underwent a pericardiectomy. Examination of surgical specimens indicated he had marked fibrosis and areas of dystrophic calcification without evidence of infection, consistent with Dialysis-related constrictive pericarditis. Hypotension for unknown causes must be considered in the differential diagnosis of dialysis patients.

IgA nephropathy in patients with serum anti-neutrophil cytoplasmic autoantibody (ANCA) positivity: case series

Some cases of patients with IgA nephropathy diagnosed via kidney biopsy and antineutrophil cytoplasmic antibody (ANCA) positivity have been reported. This article describes a case series comprising patients with IgA nephropathy and ANCA positivity seen at a medical center in the city of São Paulo, Brazil, from 1996 to 2016. A total of 111 patients underwent diagnostic kidney biopsies for IgA nephropathy. Five were ANCA-positive at the time of diagnosis; their mean age was 45 ± 15.3 years and they were predominantly females with a mean proteinuria of 2.2 ± 0.9 g/day and a median serum creatinine level of 2.5 (2.0 - 8,6) mg/dL; all had hematuria. Four of the five were cANCA-positive (80%); all had normal serum C3 and C4 levels; and 80% were positive for ANA. One case presented an association with infection, but no associations were found with medication. One patient had granuloma and another had a collapsing lesion. This article describes the cases of five ANCA-positive patients (with predominantly cANCA positivity) submitted to diagnostic kidney biopsies for IgA nephropathy; one patient had a collapsing lesion, but progressed well.

Renal Outcomes in Brazilian Patients with Immunoglobulin A Nephropathy and Cellular Crescentic Lesions

BACKGROUND AND AIM

Immunoglobulin A nephropathy (IgAN) is the most common primary glomerulopathy. The Oxford classification was recently updated to include crescents as markers of poor prognosis. The aim of this study was to evaluate the impact of cellular crescents on the prognosis of patients with IgAN in Brazil.

METHODS

This was a single-centre retrospective analysis of medical records and renal biopsies in patients with IgAN. The renal biopsy findings were classified according to the revised Oxford classification: mesangial hypercellularity, endocapillary hypercellularity (E), segmental glomerulosclerosis (S), tubular atrophy or interstitial fibrosis (T), and crescent formation (C). We evaluated a composite outcome (progression to end-stage renal disease or creatinine doubling). We performed analyses between the patients with crescents in the renal biopsy specimen (C1/C2 group) and those without such crescents (C0 group).

RESULTS

We evaluated 111 patients, of whom 72 (65.0%) were women, 80 (72.0%) self-identified as White, 73 (65.6%) were hypertensive, and 95 (85.6%) had haematuria. The distribution of patients according to cellular crescentic lesions was: C0, 80 (72%); C1, 27 (24.4%); C2, 4 (3.6%). The composite outcome was observed in 33 (29.72%) of the 111 patients. In comparison with the C0 group, the C1/C2 group had higher proportions of patients with hypertension (p = 0.04), haematuria (p = 0.03), worse serum creatinine (p = 0.0007), and worse estimated glomerular filtration rate (p = 0.0007). The C1/C2 group also had higher proportions of patients in whom the biopsy specimen was classified as E1 (p = 0.009), S1 (p = 0.001), or T1/T2 (p = 0.03), In addition, the mean follow-up period was shorter in the C1/C2 group (p < 0.0001). Furthermore, the composite outcome was observed in a greater proportion of patients and in a shorter length of time in the C1/C2 group than in the C0 group (p = 0.002 and p = 0.0014, respectively). In a Cox regression analysis, the independent risk factors for the composite outcome had Oxford classifications of S1, T1/T2, and C1/C2.

CONCLUSION

Oxford classification findings of S1, T1/T2, or C1/C2 were independent risk factors for the composite outcome, corroborating previous studies.

Atypical presentation of acute post-infectious glomerulonephritis in patients with sickle cell disease: report of two cases

BACKGROUND

Sickle cell disease (SCD) is a highly prevalent genetic disease worldwide. In the natural evolution of SCD, glomerular lesions can develop, presenting histopathological patterns of segmental or focal membranoproliferative glomerulosclerosis, with or without thrombotic microangiopathy. We report two cases of acute post-infectious glomerulonephritis (APIGN), with atypical presentations, in patients with SCD.

CASE PRESENTATION

Case 1: An 18-year-old female with SCD presented with a 21-day history of progressive oedema, accompanied by dyspnoea, productive cough, fever, and chest pain. Blood tests showed the following: haemoglobin 6.1 g/dl; leucocytes 18,820 cells/mm³; and creatinine 0.49 mg/dl. A urine sample evidenced leucocyturia and haematuria. The 24-h proteinuria was 8.99 g, serum albumin level was 1.2 g/dl, low serum C3 levels and high levels of anti-streptolysin O. Renal biopsy was consistent with APIGN. The patient was treated with diuretic and anti-proteinuric agents, subsequently evolving to reversal of the renal alterations. Case 2: A 12-year-old male with SCD presented with a 20-day history of a non-productive cough and progressive oedema, together with hypertension. The serum creatinine concentration was 0.48 mg/dl. A urine sample evidenced leukocyturia and haematuria. The 24-h proteinuria was 12.5 g, and the serum albumin level was 2.6 g/dl. The levels of C3 and C4 were normal. Renal biopsy revealed APIGN. The patient was treated with diuretic and anti-proteinuric agents, subsequently evolving reversal of the renal alterations.

CONCLUSIONS

The presentation of the two cases reported here are not typical of SCD-related kidney injury. Analysis of the renal biopsy specimens elucidated the diagnosis, affecting the prognosis, because that of APIGN is highly favourable, unlike that of nephrotic syndrome associated with SCD glomerulopathy.

Hepatoid adenocarcinoma of the lung

Lung adenocarcinomas with a mixture of tubular or papillary pattern, sheet-like or trabecular architecture, eosinophilic cytoplasm with centrally located nuclei and alpha-fetoprotein-producing cells have been described as hepatoid adenocarcinomas. Hepatoid adenocarcinomas are mainly found in the stomach but rare cases in other organs have been described. Immunostaining for alpha-fetoprotein (AFP), hepatocyte paraffin 1 (HepPar-1) and thyroid transcription factor-1 (TTF-1) helps in the diagnostic workup. Tumor behavior is still not entirely known but it seems to be associated with early metastases. We report on a 66-year-old, heavy-smoker male patient who had a 10-month history of respiratory complaints and weight loss. At the time he was hospitalized, respiratory failure was already established. The computed tomography corresponded to a collapsed right lung due to a poorly defined expanding mass. The bronchoscopy revealed narrowing of the inferior and medium lobar bronchi. The patient developed irreversible shock and died. At the right lung inferior lobe was extensively replaced by a grayish diffuse neoplasia in a “pneumonia-like” gross pattern. Metastatic disease was found in the right adrenal gland and thoracic and abdominal lymph nodes. Microscopic dissemination through lymphatics, pleura, and airways was detected. Histological examination revealed a poorly differentiated adenocarcinoma with hepatoid features. Immunohistochemmistry stains were positive for keratin 7, polyclonal carcinoembryonic antigen (CEA) in a diffuse pattern, AFP and HepPar-1 antibody. TTF-1 showed a diffuse granular cytoplasmic staining of the neoplastic cells, and only focal nuclear positivity. Multiple bilateral emboli originated from deep venous thrombosis were present in large and medium branches of the pulmonary artery and contributed to the cause of death.