Severity of lymphocytic choriomeningitis virus disease in different strains of suckling mice correlates with increasing amounts of endogenous interferon.

A marked difference was observed in the severity of disease in lymphocytic choriomeningitis (LCM) virus-infected suckling BALB/c, Swiss, and C3H mice. BALB/c mice had minimal liver lesions and none died, whereas C3H mice had extensive liver lesions and all mice died. An intermediate pattern was oberved for Swiss mice (36% mortality). Although there was no difference in the titers of LCM virus in the plasma or liver between these three strains of mice, there was a marked difference in the amount of interferon produced and the duration of interferonemia. C3H mice produced more interferon than Swiss mice which produced more interferon than BALB/c mice, indicating a direct correlation between the amount of interferon induced by LCM virus and the extent of disease. Inoculation of a potent anti-mouse interferon globulin markedly reduced the incidence of mortality in virus-infected C3H mice. BALB/c mice were as sensitive to the effects of interferon as C3H mice because daily administration of potent interferon preparations did induce disease in this strain. This ensemble of results supports our contention that endogenous interferon is in large part responsible for the manifestaions of acute LCM virus disease in suckling mice.

Antiglomerular basement membrane nephritis after solvent exposure.

A rapidly progressive glomerulonephritis with definitive anuria was observed after solvent inhalation in two young women, aged 22 and 17 years. In both cases the renal biopsy specimen showed diffuse epithelial crescents in all glomeruli, with linear deposits of IgG along the glomerular basement membrane (GBM). High circulating anti-GBM antibody levels were found in sera by indirect immunofluorescence and radioimmunoassay. No anti-alveolar basement membrane antibodies were detectable by immunofluorescent microscopy in one patient. It is suggested that the solvent inhalation resulted in a chemical alteration of the alveolar basement membrane giving rise to anti-basement membrane antibodies, some of which may have cross-reacted with the GBM and initiated the glomerulonephritis.

The morphology of "acute tubular necrosis" in man: analysis of 57 renal biopsies and a comparison with the glycerol model.

Renal biopsies from 24 patients with oliguric "acute tubular necrosis" (ATN) and 26 patients with non-oliguric ATN were compared with biopsies from 7 patients who had recently recovered from ATN and 20 control patients. Many morphologic changes were present in the biopsies of patients with ATN and absent in controls, but only two lesions were significantly more severe in patients who had ATN at the time of the biopsy compared with patients who had recently recovered from ATN. These two lesions, necrosis of individual tubular epithelial cells and loss of brush border in proximal tubules, may play a role in the pathogenesis of renal functional failure in ATN. Necrosis of individual tubular epithelial cells appeared to be a continuing process. In the patients with non-oliguric acute renal failure there was a positive correlation between duration of renal failure and severity of tubular necrosis. This was not observed in the patients with oliguric acute renal failure, but otherwise there were no identifiable morphologic differences between the two groups. The glycerol model of acute renal failure in the rabbit was found to differ in several significant ways from ATN in man. Despite the fact that the rabbits had significantly less severe renal failure, their kidneys showed much more severe tubular necrosis and much more prominent presence of tubular casts than was the case in biopsies from patients with ATN. Loss of brush border in proximal tubules was not an important feature of the glycerol model of acute renal failure in the rabbit. We suggest that the glycerol model is not analogous to human ATN and may have an entirely different pathogenesis.

Clinical significance of anti-Sm antibodies in systemic lupus erythematosus.

Case records of 34 patients with systemic lupus erythematosus (SLE) were analyzed. Twelve patients had both anti-DNA and anti-Sm antibodies (Group I) and 22 had anti-DNA antibodies only (Group II). The disease patterns were comparable, except for (1) cutaneous vasculitis, which was observed in six of 12 patients in Group I and one of 22 in Group II (p less than 0.01); (2) pulmonary manifestations, nine of 12 in Group I and two of 22 in Group II (p less than 0.001); (3) cardiac manifestations, eight of 12 in Group I and four of 22 in Group II (p less than 0.01); and (4) renal biopsy, which showed milder lesions in Group I than in Group II (p less than 0.05). Evolution was fatal in four patients in Group I and in none in Group II. It is suggested that in SLE, the presence of anti-Sm antibody is associated with a much higher incidence of vasculitis, resulting in peculiar visceral manifestations, which can be poorly responsive to therapy. Whether there is a direct association between anti-Sm antibody and vasculitis or whether the common denominator is a genetic selection remains to be determined.

Synthesis of abnormal immunoglobulins in lymphoplasmacytic disorders with visceral light chain deposition.

Three patients presented with renal or more diffuse tissue deposits of a nonamyloid material reactive with anti-kappa antibody by immunofluorescence. All patients had progressive renal failure with the nephrotic syndrome and extensive tubular basement membrane deposits. Glomerular lesions were conspicuous but heterogeneous. One patient also had hepatic deposits with peliosis at histopathologic examination. An underlying lymphoplasmacytic disorder was found in all patients: multiple myeloma in one, pleomorphic lymphoplasmacytic malignancy analogous to Waldenström's macroglobulinemia in one and bone marrow monoclonal plasmacytosis without overt myeloma in one. Biosynthesis experiments in two cases showed production of abnormal kappa chains which were not detected in appreciable amounts in serum and urine. These light chains had an aberrant size (abnormally short or large), their apparent molecular weight was larger in secretion than in cytoplasmic extracts (suggesting their glycosylation) and they were secreted as polymers. These results suggest a causal relationship between production of abnormal light chains and tissue deposition.

Renal transplantation and immunological abnormalities in thrombotic microangiopathy of adults: report of 5 cases.

Renal transplantation was performed in five adult patients with thrombotic microangiopathy, three of whom had had a bilateral nephrectomy prior to transplantation. The graft remained functional in three patients 72, 18, and 12 months after transplantation. One patient developed a thrombosis of the renal artery and one patient died from infection. There was no clinical or histological evidence of recurrence of thrombotic microangiopathy in the five patients after transplantation. Immunological investigations were performed in four of five patients before transplantation: C3 and C1q levels were low in two patients; serum C3-splitting activity and circulating immune complexes were present in all four patients and remained unchanged on haemodialysis and/or after bilateral nephrectomy. Complement abnormalities and immune complexes were not detected in the three patients with successful renal transplantation.

Interferon-induced disease in mice and rats.

Treatment of newborn mice with potent mouse interferon preparations resulted in an acute "early" syndrome characterized by inhibition of growth, delay in maturation of several organs, diffuse liver cell necrosis and death. When interferon treatment was discontinued at 1 week of life, mice appeared to recover, but subsequently developed a progressive glomerulonephritis ("late syndrome"). Treatment of newborn rats with potent rat interferon preparations also resulted in inhibition of growth, delay in maturation, and the subsequent development of glomerulonephritis. After infection at birth with lymphocyte choriomeningitis (LCM) virus, most strains of mice developed a similar acute early syndrome and surviving mice subsequently developed glomerulonephritis. We postulated that the endogenous interferon induced by LCM virus early in life was partially responsible for these syndromes. Administration of a potent anti-mouse interferon serum to LCM virus-infected mice neutralized the circulating endogenous interferon and inhibited the development of both the early and late syndromes. Our results suggest that large amounts of exogenous or endogenous interferon at a crucial stage of rapid growth or development of mice and rats can induce lesions in several different organs. Some lesions (i.e. the kidney) only become apparent weeks or even months after exposure to interferon.

A study of the presence of circulating immune complexes in schistosomiasis.

The sera from 51 patients with schistosomiasis were studied for the presence of circulating immune complexes (IC) using two methods, inhibition of EAC rosette formation and precipitation of radio-labelled Clq. The percentage EAC rosette inhibition was significantly greater in the total group of patients compared to the control sera. The material inhibiting EAC rosette formation was precipitable by 4% polyethylene glycol, thus excluding the role of C3 fragments and suggesting that inhibition was due to immune complexes. Using precipitation of radio-labelled Clq significant high values compared to control sera were only obtained in those patients before treatment or with an active infection. The results suggests that material behaving as IC is present in the sera of patients with schistosomiasis and that measurement of the levels of IC may be important in assessing the state of the disease.

Acute endocapillary glomerulonephritis in adults: a histologic and clinical comparison between patients with and without initial acute renal failure.

30 renal biopsies were performed in 20 adult patients with acute diffuse endocapillary glomerulonephritis. 11 patients who presented with acute renal failure (ARF) and 9 patients who had normal or mildly altered renal function were compared in order to look for clinical or pathologic features peculiar to each group and possible differences in outcome. All patients underwent early renal biopsy, and 8 had repeat biopsies. There were no significant differences in clinical, immunologic or histologic features between the two groups. In repeat biopsies, there were no histologic nor immunohistologic differences between patients with or without initial ARF. After a mean follow-up period of 18 months, the overall clinical outcome appeared favorable and was similar in the two groups. Thus, initial ARF in patients with acute endocapillary glomerulonephritis does not imply a bad prognosis. The recognition of pure endocapillary proliferation in patients with anuric acute glomerulonephritis by means of renal biopsy may avoid unnecessary and potentially hazardous treatment.

Deposition of fibrin-stabilizing factor (F XIIIA and S), fibrinogen-related antigens, fibrinogen degradation products (FDPd and FDPe) and antihemolytic factor (F VIII) in renal disease: analysis of 161 cases by immunofluorescence microscopy.

To see whether or not the fibrin-stabilizing factor is involved in the pathogenesis of renal damage, we analyzed by IF the glomerular deposition of factor XIII (subunits A and S) in 161 patients with various renal diseases. In 4 out of 5 cases of thrombotic microangiopathy (80%), F XIII deposits were found in a continuous subendothelial pattern, in association with deposition of fibrinogen and FDP, suggesting the occurrence of intraglomerular coagulation. In 22 out of 45 patients with membranous GN (idiopathic or SLE-associated), F XIII deposits were found along the capillary walls in a subepithelial location. These findings were not correlated with the presence of particular histological or clinical features, nor with IF positive for fibrinogen, FDP and factor VIII, suggesting alternative pathways of fibrin formation or local collagen synthesis. Finally, in proliferative GN, either idiopathic (acute post-infectious and membranoproliferative) or systemic (SLE and vasculitis), as in other glomerular and non-glomerular diseases, the presence of F XIII deposits was negligible, even in cases positive for fibrinogen, FDP and factor VIII.

Renal failure in myeloma: relationship with isoelectric point of immunoglobulin light chains.

Renal failure is a frequent but inconstant complication of myeloma related to light chain excretion. Since it has been suggested that cationic light chains (lc) are most likely to induce renal damage, we have studied the isoelectric point (pI) of light chains produced by 17 patients with myeloma and related the results to the type and severity of renal damage assessed clinically and pathologically. In order to do so, we have applied immunoenzymatic techniques which allow identification of light chain types as well as measurement of pI without prior purification. Ten of fifteen patients with renal failure produced lambda light chains. There was no simple relationship between the isoelectric point and nephrotoxicity. However, light chains with the lowest pI observed in this series were associated with normal renal function in two cases and with acute reversible but severe renal failure requiring dialysis in five cases. By contrast, pI values above 6.0 observed in the remaining patients were associated with moderate renal failure in six patients with recently diagnosed myeloma and with irreversible renal failure, and in two patients in whom myeloma had been evolutive for several years. We thus suggest that further pI measurements may help to identify light chains with different nephrotoxic potentials.

Persistent intravascular C3 activation after bilateral nephrectomy in patients with thrombotic microangiopathy.

Four patients with thrombotic microangiopathy had evidence of intravascular C3 activation on presentation which persisted after bilateral nephrectomy. In several serum samples, C3-splitting activity was not associated with the presence of circulating immune complexes, which were detected in all four patients before nephrectomy and in three after nephrectomy.

Dense deposit disease with rapidly progressive renal failure in a narcotic addict.

A girl aged 17 developed a nephrotic syndrome with renal insufficiency after narcotic abuse. Renal biopsy showed a diffuse glomerulonephritis with crescents and dense deposits within the glomerular basement membrane; glomerular C3 deposits were present without immunoglobulin. The serum complement profile was typical of activation via the alternative pathway, and tests for C3 nephritic factor were strongly positive. Terminal renal failure occurred within 6 months and required chronic hemodialysis. It is likely that the narcotics used or their contaminants were responsible for the renal damage, presumably by activating the complement system via the alternative pathway.