Silent renal microangiography after mitomycin C therapy

Mitomycin C (MMC) is an alkylating agent which has been associated with microangiopathic hemolytic anemia and acute renal failure, with an overall incidence between 2 and 10%. This complication can develop several months after the initiation of chemotherapy. Isolated renal impairment without overt microangiopathic hemolytic anemia, although reported, is less frequently documented. We describe a 63-year-old man who developed progressive renal failure without any evidence of hemolysis or thrombopenia 10 months after beginning chemotherapy with MMC and Ftorafur. A renal biopsy displayed features of microangiopathy. The patient required the institution of chronic hemodialysis. In conclusion, it is important to be aware of this indolent but severe renal complication in patients treated with MMC. Urinary parameters and renal function should be monitored over a long period for an early diagnosis.

Cellular immunity analysis using monoclonal antibodies in human glomerulonephritis

Monoclonal antibodies against class II antigens of the human major histocompatibility complex (MHC) (Edu 1), von Willebrand factor-related antigen marker of endothelial cell, T cells (Cris 1), helper/inducer T cells (T4) and cytotoxic/suppressor T cells (T8) by indirect immunofluorescence, and stain for nonspecific esterase characterizing monocytes-macrophages (Mo-Ma) were applied in 64 renal biopsies--54 glomerulonephritis (GN), 10 non-GN- and in 14 normal kidneys. Class II antigens were expressed on the endothelium of renal microvasculature in all specimens. Intraglomerular T cells and Mo-Ma were only present in GN. Mo-Ma appeared associated with endo- and extracapillary proliferation (Xc2 = 4.68; p less than 0.05), C3 (X2 = 4.21; p less than 0.05), and fibrinogen (X2 = 3.84; p less than 0.05) deposition; and those were most numerous in biopsies with intraglomerular T cells. Interstitial MHC-class II+ cells (Xc2 = 5.5; p less than 0.02), T cells (F = 3.37; p less than 0.005) and Mo-Ma (F = 2.45; p less than 0.05) were significantly higher in GN with endo- or extracapillary proliferation than in the remaining. In GN, correlations were seen between T cells and MHC-class II+ cells (r = 0.63; p less than 0.001), and Mo-Ma (r = 0.38; p less than 0.02), infiltrating the interstitium. Our results suggest that both humoral and cellular immunity contribute to macrophage glomerular infiltration in the human GN. Mononuclear cells, and no intrinsic renal cells, would be implicated in the cellular immune interactions in situ.

Renal amyloidosis with nephrotic syndrome in a Spanish subcutaneous heroin abuser

A 25-year-old drug addict who practices subcutaneous injection of heroin and crushed narcotic tablets, a practice known as 'skin popping', developed nephrotic syndrome secondary to renal amyloidosis. The patient had chronic inflammation of the skin in the form of abscesses and ulcerations. She had practiced subcutaneous drug administration for only 2 years. Amyloidosis had the staining characteristics and tissue distribution of the secondary type, and was directly related to chronic skin suppuration. To our knowledge, this represents the first reported case of renal amyloidosis in a subcutaneous drug abuser residing in Europe.

Silent renal disease in systemic lupus erythematosus

Several recent studies have focused on the discrepancy between lupus nephropathy and clinical renal involvement and, consequently, question the relevance of renal biopsy in these patients. We analyze the clinical characteristics, histological renal findings and subsequent course of patients with silent renal disease. Renal biopsy was performed in 15 patients with systemic lupus erythematosus (SLE) who had no clinical signs of renal involvement (no urinary sediment abnormalities, absence of proteinuria and serum creatinine less than 1.3 mg/dl). All biopsies were classified according to a modified classification proposed by the WHO. Six cases (40%) showed no histological or immunofluorescence changes (type I), 7 (47%) had mesangial nephropathy (3 type IIa and 4 type IIb) and 2 (13%) had focal proliferative glomerulonephritis (type III). None of the patients had previous evidence of neurological abnormalities. Patients with type I only had arthritis, skin lesions and Raynaud's phenomenon. By contrast, 7 patients with histological renal involvement had serositis or hemolytic anemia. All cases with silent nephropathy were treated with steroids and showed a benign clinical course with stable renal function and absence of urinary abnormalities during follow-up. We concluded that in the absence of clinical renal abnormalities, renal involvement is not uncommon in SLE. We believe that a renal biopsy should be performed mainly in those SLE patients presenting with clinical manifestations other than arthritis or cutaneous lesions since this policy may allow detection of significant silent renal injury.

Malignant or accelerated hypertension in IgA nephropathy

A retrospective analysis of 66 adult patients diagnosed as having IgA nephropathy by renal biopsy revealed that 24 (36%) were hypertensive when first seen. Of these hypertensive patients, 10 (15%) had malignant or accelerated hypertension. All patients but one were male and had no knowledge of their renal disease and sought medical advice for symptoms due to hypertension. Five patients had no history of gross hematuria. Histological vascular findings showed, in three proliferative endarteritis and fibrinoid necrosis, in five arteriolosclerosis and in two vascular hypertrophy. In spite of good blood pressure control, six patients reached terminal uremia within a maximum of 14 months. In summary, the incidence of malignant hypertension in adults with IgA nephropathy is higher than previously reported, and its true incidence can only be known if more histopathologic studies of patients with malignant hypertension are performed. Patients with this association reach end stage renal failure in a short period of time.

Cellular infiltrate in renal graft rejection: T lymphocyte subsets detected by monoclonal antibodies

We have examined the interstitial cellular infiltrate using monoclonal antibodies against T cells (Cris 1), helper/inducer T cells (OKT4) and suppressor/cytotoxic T cells (OKT8) by indirect immunofluorescence in renal biopsies taken from 14 transplanted patients during clinical episodes suggestive of acute (n = 9), chronic (n = 2) and no rejection (n = 3). Infiltrating T cells and T cell subsets were found to be significantly increased during all types of rejection (n = 11) as compared to no rejection (n = 3). Two types of biopsies could be distinguished according to the predominance of T cell subsets. In some biopsies (n = 6), OKT8+ cells were significantly more numerous that OKT4+ cells. In the remaining biopsies (n = 5), OKT4+ cells were more common that OKT8+ cells, the OKT4/OKT8 ratio being significantly higher. No association was observed between HLA mismatch and predominating T cell subset, neither for type nor outcome of graft rejection. Our results suggest that the OKT4+ cells may play a more important role than previously reported in renal graft rejection.

Glomerular disease in cirrhosis of the liver: low frequency of IgA deposits

Twelve HBsAg-negative patients with histologically documented cirrhosis of the liver of either alcoholic (8 of 12) or cryptogenic (4 of 12) origin underwent renal biopsy to investigate proteinuria, hematuria and/or renal failure. Immunofluorescence was positive for IgA in 2 patients with mesangiocapillary glomerulonephritis (MCGN) and could not be performed in 2 additional patients with the same diagnosis. However, in the remaining 8 patients, immunofluorescence was negative for IgA and frequently positive for C3, IgG, IgM and/or fibrinogen. These 8 patients without IgA were classified as follows: MCGN with subendothelial electron-dense deposits (2 cases), IgM-IgG cryoglobulinemia with diffuse endocapillary glomerulonephritis (1 case), membranous nephropathy (1 case), diffuse endocapillary proliferative glomerulonephritis (1 case), vasculitis with focal segmental necrotizing glomerulitis and crescentic glomerulonephritis (2 cases). These results show that cirrhosis of the liver can be associated with a wide variety of glomerular disorders. Contrary to previous belief, IgA is absent in two thirds of patients with cirrhosis and glomerulopathy. Therefore, the pathogenetic importance of IgA in the development of glomerular disease in such patients is doubtful.

Acute renal failure complicating viral hepatitis in the absence of severe hepatic insufficiency

Four patients (2 were HBsAg positive) with acute icteric viral hepatitis (VH) developed acute renal failure (ARF) in the course of their illness and in the absence of other complications. Their peak serum creatinine values (4.7-10, mean 7 mg/dl) were reached either before or simultaneously with their maximum serum aminotransferase values (1,390-2730, mean 2,032 mU/ml). Apart from VH no other factors responsible for precipitating ARF could be identified. In the HBsAg-negative patients, serological investigations for infectious mononucleosis, cytomegalovirus infection, and leptospirosis were negative. In 2 patients liver biopsy showed changes consistent with VH. Proteinuria was absent in all cases, making glomerulonephritis unlikely. The urinary sodium excretion was uniformly high (57-104, mean 78 mmol/l in random samples). Two patients required short courses of dialysis. All cases recovered completely with return of serum creatinine to normal values after a mean duration of 25 days. After a normal serum creatinine level had been achieved, 1 case was lost to follow-up, and the other 3 cases maintain normal renal and liver function tests 9 months (mean) after the initial episode. Otherwise uncomplicated VH is a potential cause of ARF, even in the absence of severe hepatic insufficiency. The mechanism of ARF in VH is unknown, but vasoconstriction phenomena induced by endotoxemia might contribute.

Relapsing polychondritis with segmental necrotizing glomerulonephritis

Glomerulonephritis is a very unusual feature of relapsing polychondritis. A 16-year-old woman presented with microscopic hematuria and severe renal insufficiency during the course of relapsing polychondritis. A renal biopsy specimen disclosed focal segmental proliferative glomerulonephritis with necrotizing lesions and crescent formation. Immunofluorescent studies suggested immune complex mediated glomerular injury. The renal involvement appeared during high-dose steroid therapy. Subsequently, she was treated by adding plasmapheresis and cyclophosphamide during 6 weeks, with sustained improvement. A regimen of plasmapheresis and immunosuppression warrants consideration for use in cases of relapsing polychondritis with glomerulonephritis.