THE HEMOLYTIC-UREMIC SYNDROME

Hemolytic-uremic syndrome after shigellosis. Relation to endotoxemia and circulating immune complexes

To investigate three possible causes of the acute hemolysis in the hemolytic-uremic syndrome, we studied prospectively 207 children and 34 adults with shigellosis in Bangladesh. Nineteen children showed acute hemolytic anemia, a leukemoid reaction, thrombocytopenia and oliguria; nine other had, in addition, a serum urea nitrogen level of over 100 mg per diciliter. Eight of the nine had pseudomembranous colitis, and six of the nine died. The frequency of bacteremia was similar in all grades of shigellosis. Circulating immune complexes were found in 10 of 20 patients with uncomplicated shigellosis and in four of six with severe hemolytic-uremic syndrome. Limulus assay for endotoxemia was positive in nine of 18 patients with hemolysis (50 per cent) and three of 61 with uncomplicated shigellosis (5 per cent) (P less than 0.001). These data support the hypothesis that severe colitis in shigellosis is associated with circulating endotoxin from the colon producing coagulopathy, renal microangiopathy and hemolytic anemia.

Colitis in children with the hemolytic-uremic syndrome

The hemolytic-uremic syndrome consists of hemolytic anemia, renal failure, and thrombocytopenia. Submucosal hemorrhage with "thumbprinting" on roentgenographic examination of the colon with barium was demonstrated in four patients, prolapse of the rectum in two patients, and pseudomembranous enterocolitis and toxic megacolon in one. These lesions are not generally associated with hemolytic-uremic syndrome. The presence of these lesions in a child with bloody diarrhea should suggest hemolytic-uremic syndrome as a possible diagnosis. Sigmoidoscopy and roentgenographic examination of the colon with barium should be done in selected patients with hemolytic-uremic syndrome to evaluate the degree of colonic involvement and the need for surgery.

Microcalorimetric measurements of heat production in erythrocytes of patients with chronic uraemia

The metabolic activity in the erythrocytes of 12 patients with chronic uraemia was studied by a microcalorimetric method. When the pentose phosphate pathway activity of erythrocytes was stimulated with 10(-4) M methylene blue (MB), significantly higher levels of heat effect were found in the group of uraemic patients than in a group of healthy subjects. The difference between the 2 groups was higher in plasma (p less than 0.005) than in phosphate buffer suspensions (p less than 0.05). The ratio between the mean values for the 2 groups was 1.18 both in plasma and in phosphate-buffer. Also for unstimulated cells the heat effect values were higher in the group of uraemic patients than in the control group. The ratio was 1.21 (p less than 0.005) and 1.14 (p less than 0.05) for plasma and buffer suspensions, respectively. The present results are in disagreement with previous reports, according to which haemolytic anaemia among uraemic patients is due to decreased erythrocyte aerobic metabolism.

Transplantation in the hemolytic-uremic syndrome

A case history of a fifty-seven-year-old white woman with hemolytic-uremic syndrome who was successfully transplanted with a cadaver homograft is reported. A review of the pertinent literature regarding the pathophysiology of the syndrome and the experience to date with transplantation is presented.

Thrombotic thrombocytopenic purpura in childhood

A survey was conducted among 46 pediatric institutions in the United States and Canada to evaluate the presentation, therapy and survival of children with thrombocytopenic purpura (TTP) seen since 1960. TTP is an uncommon disease in the pediatric age group, and the clinical and pathologic findings in adults and children are almost identical. It can be distinguished from haemolytic uraemic syndrome in that it usually occurs in older children, the renal disease is milder, and the central nervous system symptoms appear to be related to vascular occlusive disease, and not to the complications of severely compromised kidneys. Appropriate biopsy specimens which reveal typical widespread hyaline occlusion of arterioles may confirm the diagnosis. Combinations of corticosteroids, splenectomy, and heparin have been used as therapy. Prognosis has improved, and is probably related to improved supportive care.

Thrombotic thrombocytopenic purpura in four siblings

A family is described in which four members of a sibship of seven suffered from a hematologic and systemic disorder whcih has been fatal in three and has been proved at autopsy to have been fatal in three and has been proved at autopsy to have been thrombotic purpura. The fourth member has probably suffered the same disorder. The clinical laboratory and genetic features of the family are discussed at length. No cause of the disorder has been determined.

Haemolytic-uraemic syndrome. Epidemiological and clinical study

Between January 1965 and December 1970, 212 patients with the haemolytic-uraemic syndrome in the Netherlands were analysed in an epidemiological and clinical study of the disease. The disorder typically occurs in early infancy, in children without antecedent illness. The majority of the patients were younger than 4 years. The incidence of the disease in the Netherlands is increasing. The disease occurs throughout the year but peak incidences were noted during the late spring and early summer. Apart from this seasonal influence there was a geographical clustering. The possible relation of the epidemiological features of the syndrome to a viral aetiology is discussed.

Hypertension in Nigerian children

A retrospective review of 138 cases of hypertension in Nigerian children attending the University College Hospital, Ibadan, during a 9-year period was undertaken. The main findings were (a) that hypertension occurs more commonly in children aged 5 to 10 years and is seen in both sexes; (b) that nephrotic syndrome is the most frequent clinical condition associated with hypertension in these children; (c) that glomerulonephritis is the most frequent histological finding at biopsy or necropsy; (d) that unlike the experience in Europe and America, pyelonephritis is not a major cause of hypertension in Nigerian children; (e) that the course of hypertension in the majority of the children is rapidly progressive and prognosis is poor.

Haemolytic-uraemic syndrome treated with heparin

Three children with the haemolytic-uraemic syndrome were treated with intravenous heparin. Peritoneal dialysis was required for two of them, one of whom died after 26 days of therapy. Renal biopsy specimens from the two survivors showed widespread glomerular disease, which appeared permanent in one case, but only occasional thrombi. It is suggested that heparin therapy, by preventing further intrarenal thrombosis, allowed the normal fibrinolytic mechanisms to remove previously formed thrombi.

Fatal haemolytic-uraemic syndrome in two sibs

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The haemolytic uraemic syndrome--an epidemic disease?

Six cases of the haemolytic uraemic syndrome occurring in the same district during a period of 27 months are described. No aetiological agent was identified. With symptomatic treatment four children recovered completely. Two children died, one after a fulminating illness lasting 6 days and the other after an illness lasting three months.

Early diagnosis of thrombotic microangiopathy by paraffin sections of aspirated bone-marrow

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