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Mysterious deaths of archeologists after opening Egyptian tombs have been suspected to be secondary to inhalation of mycotoxin, however, the hypothesis has never been verified. Recently, we observed a case of acute renal failure (ARF) undeniably due to inhalation of ochratoxin of Aspergillus ochraceus. After spending 8 h in a granary which had been closed for several months, a farmer and his wife suffered temporary respiratory distress; 24 h later, the woman developed nonoliguric ARF and biopsy revealed tubulonecrosis which healed in 24 days. Toxic substances were not found, but a strain of A. ochraceus producing ochratoxin was isolated from the wheat.

Human and rabbit peritoneal mesothelial cells have been successfully cultured and autoimplanted. An original biopsy technique was used to take samples of peritoneal mesothelial cells and after culture they were characterized from the structural and caryological points of view. Staphylococcal peritonitis was induced in 12 rabbits with indwelling peritoneal catheters and after 4 days of antibiotics 6 of them were autoimplanted with cultured autologous mesothelial cells previously marked in 3 cases with thymidine (H3TdR). Direct morphological observation and autoradiography were used to compare the mesothelium of control rabbits and implanted rabbits sacrificed on days 3 and 6 and showed that the cell implants had taken. Four uremic CAPD patients recovering from severe peritonitis were implanted with about 300 million autologous peritoneal mesothelial cells, previously cultured and frozen. Morphological signs of taking were evident from peritoneal laparoscopy biopsies performed 3 and 6 days after implant. The aim of the study was merely to demonstrate that such implants are possible; however, the techniques may have interesting applications not only in peritoneal dialysis, but also in the vaster fields of medicine and surgery.

Nine new cases of double glomerulopathies (GP) were found among 1,715 renal biopsies. Immunofluorescence and electron microscopy were needed to achieve a correct diagnosis and the prevailing relevance of these techniques in single cases was stressed. IgA nephropathy was the most commonly found GP, being associated with membranous glomerulonephritis (GN) (2 patients), minimal change disease (3 patients), and focal segmental glomerulosclerosis (1 patient). In addition, single cases of membranous GN plus crescentic GN and acute GN plus cryoglobulinemic GN were recorded. Possible factors involved in the pathogenesis and clinical significance of double glomerulopathies are discussed.

Eight patients belonging to 3 unrelated families had biopsy-proven IgM mesangial nephropathy. In the first family, the mother and the 2 daughters were affected; in the second, the mother and the son; in the third, 2 sisters and the brother. Two additional sisters of the third family showed a clinical picture consistent with chronic glomerulonephritis. The clinical picture was that of hematuria and/or proteinuria. No patients had nephrotic syndrome. Genealogic investigation enabled us to discover 2 additional affected members in the kindred of the first family (1 with IgA nephropathy, 1 with clinical glomerulonephritis) and 3 other affected members in the pedigree of the third family (1 with IgA nephropathy, 1 with sclerosing glomerulonephritis, 1 with clinical glomerulonephritis). Immunogenetic studies showed the recurrence of an extended haplotype bearing DR beta 11-DQ beta 3B-DQ alpha 2-C4A3-C4B1-BfS in 9 of 10 affected members. Our data suggest that genetic factors may be involved in the mechanism of the disease and support the hypothesis that IgM nephropathy is a distinct disease entity.

The localization of dopamine receptors within rabbit renal artery was studied using 3H-spiroperidol as a label for dopamine receptors and a histoautoradiographic technique. Preliminary radioreceptor binding studies showed that 3H-spiroperidol was bound to sections of renal artery in a manner consistent with the existence of dopamine receptors. In fact the binding was found to be saturable, stereospecific and of high affinity, with a Bmax approximately of 158.3 fmol/mg protein and a Kd of 13.5 nmol/l. The microscopic examination of sections processed for the histoautoradiographic demonstration of 3'-spiroperidol binding sites showed that the distribution of dopamine receptors in the renal artery was widespread. The highest concentration of dopamine receptors was found primarily in the smooth muscle cells of the media and then, in the following order, in endothelial cells of the intima and in fibrous and connective cells of the adventitia. The direct demonstration of dopamine receptors in the media of rabbit renal artery strongly supports the hypothesis that these receptors may be involved in the relaxation of the artery caused by infusion or application of dopamine.

The traditional diagnostic approach to immunologically mediated glomerulonephritis is based on the morphological (both in light and electron microscopy) and immunofluorescence examinations of different samples of the same renal biopsy. A major disadvantage of this composite procedure is represented by the inability to precisely correlate the immunocytochemical data with the presence and distribution of electron-dense deposits. Immunoelectron-microscopic techniques could therefore represent a more useful tool for immunomorphological investigations into these glomerulopathies. In order to overcome the significant limitations of preembedding staining procedures, we introduce two postembedding staining techniques (using peroxidase or colloidal gold as markers of the immunoreaction) which result in a precise immunolocalization of immunoglobulins in the dense deposits of glutaraldehyde-fixed, postosmicated and Epon-embedded renal biopsies, while adequately preserving the ultrastructural morphology of the tissue sections.

In the last 3 years we performed 52 peritoneal biopsies (PB) in 31 patients on continuous ambulatory peritoneal dialysis (CAPD). Samples of the parietal peritoneum were obtained either during insertion of the catheter or while it was being repositioned or removed. PB was performed in 13 patients before initiating CAPD and in 27 after 7-49 months of CAPD while 7 had PB during peritonitis, and, again, in 5 of these cases, PB was repeated after 1-4 months for light, electron transmission, and scanning electron microscopy. BP after CAPD showed that mesothelial cells were irregularly spaced, and at times we observed alterations in the cellular structure. Rarely were these cells degenerating, while rarefaction and in many cases complete absence of microvilli were observed. In some cases the submesothelial layers showed rarefaction of the connective tissue and sclerosis. During peritonitis, PB showed more alterations with marked degeneration and in some cases necrosis of the mesothelium and alterations of connective tissue. PB performed some months after peritonitis showed only a partial regression of these alterations and sclerotic patches, and no microvilli were noted in the mesothelium.

A patient with echinococcosis, acquired deficiency of the inhibitor of the activated first component of complement and angioedema symptoms has been studied. These symptoms started 7 months after the surgical removal of an echinococcus liver cyst. Eight years later, when the complement was investigated, a marked deficiency of the C1 inhibitor, C1, C4 and CH50 was present. The patient was therefore successfully treated with tranexamic acid. After 4 years, the woman needed another operation because of a relapse of echinococcosis; afterwards she was symptom-free without medications, while the complement profile remained unchanged. Circulating immune complexes were detected by the conglutinin method. The patient's serum was demonstrated to possess an anticomplementary activity without affecting the C1 inhibitor when incubated with normal human serum at 37 degrees C. At present, 16 years after the onset of the symptoms, there are no signs of lymphoproliferative disease.

Adriamycin induces a nephrotic syndrome in rats characterized by severe ultrastructural changes of visceral epithelial cells similar to those observed in puromycin aminonucleoside (PA) nephrosis and in human 'minimal changes' glomerulopathy. Since steroids have been shown to be effective in human 'minimal changes' glomerulopathy and in PA nephrosis, we undertook the present study to assess whether steroids had a therapeutic effect on adriamycin nephrosis. Groups of rats injected with different doses of adriamycin were subsequently treated with prednisolone. No significant differences were observed in proteinuria and in ultrastructural findings between the control and the steroid-injected animals. This study suggests that the mechanism underlying adriamycin-induced nephrotic syndrome might be different from that responsible for PA nephrosis or human 'minimal changes' glomerulopathy.

22 renal biopsies of 22 patients with 6-month-old transplants have been examined at the light- and electron-microscopic level to demonstrate the toxic effects induced by ciclosporin A (CS). These patients presented stable renal function and were exempt from acute rejection symptoms or nephrotoxicity. Interstitial fibrosis, tubular atrophy and interstitial lymphocytic infiltration were the lesions most often observed by light microscopy. In a single case an arteriolar lesion suggestive of arteriolopathy due to Cs was seen. Ultrastructural observations of renal tubular cells showed a tendency of rough and smooth endoplasmic reticulum to microdilate and microvacuolize. In 4 out of 22 cases there were mitochondrial alterations with giant mitochondria. In only 1 case, clusters of cilia were seen. Clinical histological correlations show that interstitial fibrosis is directly proportional to CS blood level. CS higher blood levels suggest a higher risk of nephrotoxicity.