Giuseppe Passavanti

Endotoxemia in Hemolytic Uremic Syndrome

Hemolytic uremic syndrome (HUS) was diagnosed and confirmed by renal biopsy in an 18-year-old primigravida at the 13th week of pregnancy. Circulating endotoxin was detected and the endotoxemia was progressively reduced by hemodialysis (HD) performed daily from the 3rd to the 9th day of disease. Complete normalization of the renal function was observed on day 34. The authors emphasize the importance of detecting endotoxemia in HUS in order to initiate dialysis early; at the same time they also discuss the pathogenetic role of endotoxin in this disease.

Prognosis in Acute Renal Failure Accompanied by Jaundice

The mortality rate of 67 sequential cases of acute renal failure (ARF) accompanied by jaundice was compared with the mortality rate of 168 patients without jaundice. The mortality rate in the group of jaundiced patients was 57%, significantly greater (p less than 0.05) than the 42% mortality in patients without jaundice. The mortality rate correlated with serum bilirubin levels; patients with serum bilirubin greater than 20 mg% had a mortality rate of 85%, whereas patients with levels lower than 10 mg% had a mortality rate of only 33%. Average blood pressures were significantly lower (p less than 0.01) in patients with jaundice than in those without. The data indicate that: (1) ARF accompanied by jaundice carries a worse prognosis; (2) reduced blood pressure which accompanies this condition may be an aggravating factor, and (3) serum bilirubin levels may be used as a prognostic index.

Acute renal failure after septic shock.

The problem of sepsis and acute renal failure(ARF)remains to date a major unsolved challenge to nephrologists. Despite the regular use of dialysis and other major improvements in the management of patients (pts) with ARF,mortality continues to be distressingly high(1,2).

Role of Endotoxin in Hepatorenal Syndrome

It is known that patients affected by liver cirrhosis may develop functional renal failure induced by circulatory disorder of the kidney, likely due to active vasoconstriction with reduction of cortical perfusion (1), and characterized by reduced glomerular filtration rate with intact tubular function. In fact the urine sodium concentration in these patients is extremely low, usualy less than 10 milliequivalent per liter, and urine sediment is relatively unremarkable. This type of renal failure is called hepatorenal syndrome (HRS) and many factors have been considered in its pathogenesis, including activation of the renin — angiotensin system due to reduced “effective” blood volume (2,3,4), increase in sympathetic nervous system activity (5,6,7,8), alterations in the endogenous release of renal prostaglandins (9,10,11,12,13,14,15) and changes in the kallikrein-kinin system (16).

Prognostic determinants in lupus nephritis.

The prognostic of SLE has progressively improved, especially during the past decade (1), and considerable advance has been made in the prognosis of lupus nephritis as well.

Lithium Induced Polyuria and Polydipsia

It is well known that lithium carbonate, which is frequently used in the treatment of psychiatric disorders,can induce a syndrome characterized by polyuria and polydipsia (1). According to the various investigators, these clinical findings appear in a range between 20% and 70% of the patients treated (2,3,4,5,6,7). Lithium-induced polyuria and polydipsia may be due to primary polydipsia with secondary polyuria or to primary polyuria with secondary polydipsia. In support of the above-mentioned alternatives, it has been reported that lithium may stimulate thirst or may interfere with the ADH-dependent mechanisms. Experimental studies on rats have demonstrated that lithium can stimulate thirst (8,9,10,11). Other experimental studies on rats have demonstrated that lithium can deplete the posterior pituitary gland and the supra-optic nuclei of their neuro-endocrine material (12,13), showing that lithium may interfere with the synthesis, deposit and/or release of the ADH hormone, causing central diabetes insipidus. On the other hand, another cause which has been suggested is an interference by the lithium with the tubular renal action of the ADH, causing nephrogenic diabetes insipidus (14,15,16,17). In contrast, however, some authors were unable, under somewhat different experimental conditions, to detect a lithium-induced inhibition of the ADH -stimulated water flow in toads’ urinary bladders (18).

Incidence of human immunodeficiency virus antigenaemia in patients on haemodialysis.

P. Coratelli, MD, Institute of Nephrology, University of Bari P.G. Cesare, I-70100 Bari (Italy) Dear Sir, Patients on regular dialysis treatment (RDT) are in a high-risk group of acquiring human immunodeficiency virus (HIV) infections by blood transfusions, blood contaminated equipment of after kidney transplantation [1–3]. HIV antigen seems to appear in serum some weeks before antibodies become detectable, and while HIV infection is on the increase, antibody screening cannot exclude an early stage of infection. We tested 143 sera of patients on RDT for the presence of HIV antigen by Abbot enzyme immunoassay at time 0 and after 9 months. Specificity was checked by a neutralization test with prior treatment of serum by a human policlonal antibody to HIV. Two sera were repeatedly reactive (1.4%) but only one of them could be neutralized by pretreatment with specific antibody indicating positive reaction. Positivity was confirmed also after 9 months of observation. The patient with HIV antigen positivity had no risk factors for HIV infections, received 3 blood transfusion units in the last 2 years, and presented no clinical symptoms of AIDS or ARC. Seroconversion cannot be detected after 9 months. The clinical data of the HIV antigen-positive patient are illustrated below. The detection of virus antigen in the serum from uremic patients infected with HIV can supplement tests for antibodies in diagnosis of HIV infection because antigens are often detectable in blood many months before antibodies appear and with the absence of clinical symptoms. We conclude that the HIV antigen test should be used to close the diagnostic ‘window’ between infection and antibody production that in haemodialysed patients can be greater for uremic immunosuppression or delayed immunoresponse.

Effect of Bicarbonate Haemodialysis on Peripheral Oxygen Availability in Mild Hypertensive Patients

Reduced peripheral oxygen availability is often observed in nephropatic hypertensive patients who require periodical haemodialysis and more often in patients with peripheral occlusive arterial disease (POAD). The aim of this study was to evaluate the effect of bicarbonate haemodialysis on peripheral oxygenation using transcutaneous pO2 electrodes in a group of patients with mild hypertension (not treated with anti-hypertensive drugs) and POAD.

Renal Impairment in Uric Acid Excretion in Patients with Primary Gout

The renal handling of urate has been studied in 32 patients with gouty nephropathy and in 32 non-gouty nephropathic control patients,by evaluating the filtered urate Load, uric acid excretion, uric acid clearance and uric acid excretion fraction.

Drug-Induced Tubulo-Interstitial Nephritis

Acute interstitial nephritis (AIN) is by far the most common pattern of immunologically mediated renal injury and is associated with an ever-expanding number of pharmacologic agents (1,2). Antibiotics, diuretics and nonsteroidal anti-inflammatory agents (NSAID)are among the more commonly reported drugs responsible for causing AIN (3, 4, 5).