Attack rate of poststreptococcal nephritis in families. A prospective study

Twenty-two families comprising 141 first-degree relatives (42 parents and 99 siblings) were studied prospectively after the appearance in the family of an index case with acute poststreptococcal glomerulonephritis (APSGN). There was no epidemic when the studies were conducted. Families were observed weekly for 4-6 weeks after the appearance of the index case, and at least every 6 months thereafter for 1-3 years. At each examination all members of the family gave a history and had a physical examination, urine analysis, and appropriate cultures; antistreptococcal antibody titres and serum C3 were determined. 33 parents and 95 siblings showed changes in antistreptococcal antibody titres suggestive of infection during or shortly before the period of weekly observation. Group A streptococci of various M and T types were isolated from 17 individuals in 14 families. 25 cases of clincal APSGN (including 22 index cases) and 12 cases of asymptomatic APSGN were detected. The results indicate that within families the streptococci responsible for nonepidemic APSGN are very infectious. The subclinical/clinical disease ratio (excluding index cases) was 4.0. The high attack rate (37.8%) in 77 sibling contacts at risk may indictae that susceptibility to nephritis after streptococcal infection is a familial trait.

[Levels of lactate dehydrogenase isoenzymes in the serum of Hansen's disease patients]

The LDH isoenzymes levels in fresh serum of seven patients affected by different forms of hanseniasis from Argentina, were measured by acrylamide electrophoresis. In all cases the LDH-4 fraction was found elevated; on the contrary, LDH-2 was reduced. The LDH-5 fraction was detected in only three serums, all of them significantly increased when compared with controls.

Evidence of an immediate hypersensitivity mechanism in systemic lupus erythematosus

In 30 patients with systemic lupus erythematosus the number of a circulating basophils was countered in different stages of activity. An inverse correlation was found between the absolute basophils count and anti-DNA antibodies and presumptive circulating immune complexes (as judged by polyethylene glycol precipitation of serum). A positive correlation was found between the absolute basophil count and C3 or C4 levels. IgE on the basophil surface was determined by radioimmunoassay in 7 patients. All of them showed a significantly higher surface IgE number. When the count of circulating basophils was roughly normal, 5 out of the 6 patients showed a positive basophil degranulation test with native DNA. These results suggest the existence of an anti-DNA specific IgE in lupus patients. Depression of the circulating basophil count may be a useful index of lupus activity.

Evidence of sensitized basophils in renal transplanted patients

The participation of basophil polymorphonuclear leukocytes in the response to kidney allografts in man has hardly been studied. In 23 patients, followed from the immediate post-transplant period for several years, the number of circulating basophils, expressed either as absolute number or as percentage of leukocytes, was significantly low in relation to that of controls. IgE on the basophil surface was determined by radioimmunoassay in 14 patients. All patients but one had elevated numbers of IgE molecules per basophil, values being higher in patients with cadaver grafts and in patients with a graft functioning at 6 months or less. When the count of circulating basophils was roughly normal, six of the eight patients showed a positive basophil degranulation test against the donor lymphocytes. These results suggest the existence of specific IgE antibodies for HLA antigens in renal transplanted patients.

Characterization of the glomerular antibody in acute poststreptococcal glomerulonephritis

Glomerular-fixed antibody was eluted from the kidney of a 17-year-old patient who died 2 weeks after the onset of acute poststreptococcal glomerulonephritis. Elevated titers of antibodies to streptococcal enzymes were found in the serum but not in the glomerular eluate. Streptococcal M protein and anti-M protein reactivity were not detected in the eluate. Immunoglobulin G was the only serum protein demonstrated in the eluate, and it was found to have anti-IgG activity highly concentrated with respect to the serum. These studies appear to indicate that anti-IgG is involved in the immune pathogenesis of acute poststreptococcal glomerulonephritis. Native IgG may be rendered autoimmunogenic by the streptococcus with subsequent antibody production to the neoautoimmunogen. Alernatively, anti-IgG may be produced to the IgG incorporated in an exogenous streptococcal antigen-antibody complex.

Circulating immune complexes and serum immunoglobulins in acute poststreptococcal glomerulonephritis

Acute poststreptococcal glomerulonephritis (APSGN) is a disease thought to be induced by the renal deposition of circulating immune complexes. In order to test this possibility, serum samples from 119 patients with APSGN were studied for Clq binding activity (ClqBA), levels of IgG, IgM, IgA, C3 and antibody titers to streptococcal enzymes. These parameters were analyzed in relation to the clinical and laboratory data of the acute nephritic syndrome and with respect to the time elapsed from streptococcal infection and from the onset of nephritis. Elevated ClqBA was found in 66.7% of the patients in the first week of the disease and this frequency decreased progressively to 17.6% after the second week. Normal ClqBA was found in patients after the third week of nephritis. Serum levels of IgG and IgM were elevated in over 95% of the patients. Levels of IgG in excess of 2400 mg/dl were detected in 71.1% of the cases. No correlation could be found between the ClqBA and the clinical or immunoserological findings of the disease. The data support the hypothesis that circulating immune complexes are responsible for the nephritis that follows streptococcal infection.

[Perinatal morbimortality]

Between 1972 and 1975 (4 years), the Hospital de Ginecoobstetricia "Dr. Ignacio Morones Prieto" of the I.M.S.S. at Monterrey, N.L., reported a birth rate of 106, 771 with 98.35% (105,004) live borns. The morbidity rate was 262.06/1000 live borns and the perinatal mortality was 31.24/1000, divided into antenatal 16.54/1000 and posnatal 14.70/1000. Within morbidity, prematurity and/or low weight occupies the first place, followed by respiratory pathology and afterwards, jaundice, infections, obstetric trauma and finally, congenital malformations. The neonatal mortality reached 14.70/1000 live borns and if we consider gestational age, 22.9% corresponds to immature products, 50.2% prematures and 26.0% to full-term products. In relation to hours of life, we find that 62.50% of the total number of deaths were reported in products less than 24 hrs. of life and 37.50%, in products over 24 hrs. of life.

H2 breath tests during diarrhea

The peak rise in breath hydrogen and the volume of excess pulmonary excretion of hydrogen in response to a 10 g dose of the non-abosorbable disaccharide, lactulose, was significantly lower in children with active gastroenteritis and diarrhea than in nondiarrheal controls. Thus, despite the fact that the H2 breath test is a convenient, noninvasive technology for use in children, it cannot be recommended for measuring carbohydrate malabsorption in individuals with active, on-going episodes of diarrhea.

Evidence of an autologous immune complex pathogenic mechanism in acute poststreptococcal glomerulonephritis

Clinical and experimental studies have suggested a role for antiimmunoglobulins in the pathogenesis of glomerulonephritis associated with streptococcal infection. We attempted to localize anti-IgG in the kidneys of 22 patients who had renal biopsies performed 7 to 66 days after the onset of acute poststreptococcal glomerulonephritis (APSGN). In addition to routine localization of immunoglobulins and C3, specimens were stained with neuraminidase-treated, heat-aggregated, and unmodified IgG. Twelve biopsies showed staining with fluorescein-labeled human neuraminidase-treated IgG. A lesser number gave positive staining with the other IgG preparations. Following treatment of slides with 0.01 M citrate buffer, seven previously negative biopsies showed positive staining with neuraminidase-treated IgG. The demonstration of anti-IgG by these methods was possible in 19 out of 22 biopsies. It correlated best with the presence of C3 and IgG, and to a lesser extent with IgM, in the renal glomerulus. These results and our previous finding of elevated levels of serum anti-IgG early in the course of APSGN, and as early as 8 days following the antecedent streptococcal infection, support a role for anti-IgG in the immune pathogenesis of APSGN. Although our series of studies support the hypothesis that anti-IgG is formed to an IgG modified enzymatically by streptococcal product, the formation of this autoantibody to IgG incorporated in an exogenous (streptococcal antigen-antibody) complex can not be ruled out.

Immunopathology of the skin in acute poststreptococcal glomerulonephritis

The immunohistologic features of the skin were studied in 26 cases of poststreptococcal glomerulonephritis. Twenty-two patients had vascular and extravascular dermal deposition of IgG. Positive stains for C3 (eight patients). IgM (two patients), and fibrinogen (five patients) were confined to vessel walls. Staining with anti-IgA serum was uniformly negative. Circulating antiskin antibodies could not be detected. Extravascular accumulation of IgG has a widespread distribution in the dermal papillary layer that is highly characteristic. It was absent in 7 patients with chronic glomerulonephritis and in 11 patients with various other renal diseases. The described findings appear to occur consistently in acute poststreptococcal glomerulonephritis. The distinctive extravascular demonstration of IgG may prove to be valuable in the diagnosis of this entity.

Effects of triiodothyronine on the anemia of chronic renal failure

The present study was done in order to determine whether treatment with triiodothyronine (T3) would improve the anemia of chronic renal insufficiency. Four patients with stable renal failure and anemia were treated with 75 microgram/day of T3 for a period of four weeks. The patients were not in chronic dialysis, had normochromic normocytic anemia and hypocellular bone marrow, and showed no evidence of external blood loss during the study. They had received no iron, folic acid, or androgenic steroids for at least six months prior to the study. The administered dose of T3 was adequate to depress the serum levels of thyroid-stimulating hormone (TSH); however, there was no detectable improvement in the levels of hemoglobin, hematocrit, bone marrow cellularity, serum and erythrocyte folate determinations, serum iron (Fe), 59Fe half-life, plasma iron turnover rate, percentage Fe incorporated into red blood cells, or in the ratio of surface radioactive counting over bone marrow/liver and spleen. It is concluded that the experimental observations concerning direct bone marrow stimulation by T3 in anephric rats are probably not clinically applicable for the treatment of the anemia associated with uremia.

Immunohistologic findings in the lung in systemic lupus erythematosus

A 29-year-old woman with systemic lupus erythematosus (SLE) developed dyspnea, hemoptysis, pleuropericarditis, and azotemia shortly after an episode of arthritis and progressive hair loss. She had a high titer of radioimmune anti-DNA Antibodies, positive fluorescent anti-smooth muscle antibodies, and depressed C3 levels in her serum. Antiglomerular basement membrane antibodies were negative, and the titer of antibodies against extractable nuclear antigen was within normal limits. Cryoglobulins and lupus erythematosus cell preparations were negative. Despite steroid therapy and other supportive measures, including dialysis, she died ten days after admission. Percutaneous renal and pulmonary biopsies were performed postmortem at bedside and were processed for immunohistology. Identical granular deposits of C3 and IgG were found in both the lungs and the kidneys. This finding suggests that a common pathogenetic mechanism is operating in the development of pneumonitis and nephritis in SLE, and is in agreement with the currently held views on immune-complex diseases.

Kallikreinlike activity in perfusates and urine of isolated rat kidneys

In the perfusate and the urine produced during perfusion of isolated rat kidneys a kallikreinlike enzyme similar to that found in the kidney was detectable by bioassay 15-25 min after the beginning of the perfusion. The source of the kallikrein activity was the kidney itself, since before the perfusion was started the blood remaining in the kidneys was washed out and the perfusion medium was free of kallikrein and its precursors and substrates. The kallikreinlike activity of the perfusate was characterized by a) an oxytocic effect on isolated rat uterus, b) a kininogenase activity on kininogen II, c) an esterase activity on N-benozyl-L-arginine ethyl ester, and d) a hypotensive effect on anethetized rats. These properties were inhibited by diisopropyl activity in the perfused kidney was lower than that in the nonperfused organ, but the total amount of kallikrein activity released to the excreted urine and the perfusate was significantly greater than the corresponding activity that disappeared in the kidney. This result is in keeping with the concept that the renal tissue is able to synthesize kallikrein.