Acute peritoneal dialysis, complications and outcomes in 389 children with STEC-HUS: a multicenter experience

BACKGROUND

Management of acute kidney injury (AKI) in children with hemolytic uremic syndrome induced by a Shiga toxin-producing Escherichia coli infection (STEC-HUS) is supportive; however, 40 to 60% of cases need kidney replacement therapy (KRT). The aim of this study was to analyze procedure complications, especially peritonitis, and clinical outcomes in children with AKI secondary to STEC-HUS treated with acute PD.

METHODS

This is a multicenter retrospective study conducted among thirty-seven Argentinian centers. We reviewed medical records of 389 children with STEC-HUS hospitalized between January 2015 and February 2019 that required PD.

RESULTS

Complications associated with PD were catheter malfunction (n = 93, 24%), peritonitis (n = 75, 19%), fluid leaks (n = 45, 11.5%), bleeding events (n = 23, 6%), and hyperglycemia (n = 8, 2%). In the multivariate analysis, the use of antibiotic prophylaxis was independently associated with a decreased risk of peritonitis (hazard ratio 0.49, IC 95% 0.29-0.81; p = 0.001), and open-surgery catheter insertion was independently associated with a higher risk (hazard ratio 2.8, IC 95% 1.21-6.82; p = 0.001). Discontinuation of PD due to peritonitis, severe leak, or mechanical complications occurred in 3.8% of patients. No patient needed to be transitioned to other modality of KRT due to inefficacy of the technique. Mortality during the acute phase occurred in 2.8% patients due to extrarenal complications (neurological and cardiac involvement), not related to PD.

CONCLUSIONS

Acute PD was a safe and effective method to manage AKI in children with STEC-HUS. Prophylactic antibiotics prior to insertion of the PD catheter should be considered to decrease the incidence of peritonitis.

[Severe Henoch-Schonlein purpura in a patient with multiple myeloma]

A Multiple Myeloma (MM), IgG-lambda stage III-A was diagnosed in a 41-year-old-man. After VAD cycles IgG decreased from 7.5 to 2.4 g/dL. were mobilized with cyclophosphamide and 10 micrograms/Kg G-CSF. Three days after the collection of peripheral stem cell, the patient had fever, nausea, vomiting, liquid stools, shoulder and knee arthralgia and dehydration. Upper GI endoscopy showed esophageal candidiasis and ulcerative necrotic lesions both in stomach and duodenum; the biopsy confirmed necrosis. Simultaneously, the appearance of purpura with maculopapular lesions of diverse sizes appeared in the feet progressing to the limbs and trunk. Hematuria and proteinuria were also observed. Skin biopsy showed leukocytoclastic vasculitis. Renal biopsy showed focal and segmental glomerulonephritis. Serum ANCA, cryoglobulins, anti-HCV and RF were negative, and serum monoclonal IgG was 1290 mg/dL. Daily treatment with i.v. methylprednisolone pulses for 3 days improved skin lesions and digestive involvement. Macroscopic hematuria and proteinuria improved after two months of steroid treatment.

[Antigenic and genomic characterization of Herpes simplex virus isolated from double genital infections]

Two Herpes simplex viral serotypes, HSV type 1 and HSV type 2 may cause genital herpes. The aim of this study was to perform a genetical analysis and characterization of virus isolated from four patients with double genital herpetic infections. In eleven viral isolates, the cytopathic effect in Vero cells was studied, the antigenic type was determined using monoclonal antibodies and genomic analysis was performed with Eco RI, Hind III and Bgl II enzymes. Five viral isolates generated a diffuse and 6 a localized cytopathic effect. Monoclonal antibodies identified four HSV-1 and seven HSV-2. Genomic analysis had concordant results. Four HSV-1 were obtained, with different genomic patterns within them, three were different to the standard North American strain. The seven HSV-2 obtained had three different types of electrophoretic profiles, that were different to the standard North American strain. It is concluded that the genomic and antigenic analysis allowed the detection of herpetic genital infections caused by herpes virus type 1 and 2 in the same individual and the identification of herpes virus strains with distinct regional characteristics.

Trypanosoma cruzi: trypanocidal effect of 2(3)-tert-butyl-4-hydroxyanisole (BHA) on several strains of epimastigote and trypomastigote forms

BHA (2(3)-tert-butyl-4-hydroxyanisole) produced inhibition of both culture growth and oxygen consumption, NAD(P) reduction and cytochrome b oxidation, on intact epimastigotes of Trypanosoma cruzi. BHA inhibited respiration and reduced NAD(P) in intact T. cruzi trypomastigotes. Oxidative phosphorylation of in situ mitochondria of epimastigotes was inhibited by BHA and this effect was liberated by the addition of ascorbate+TMPD. The incorporation of rhodamine-123 to mitochondria of living epimastigotes was diminished by BHA. These results suggest that the basis of the trypanocidal effects of BHA could be due to the blockage of the mitochondrial electron transport chain on the segment previous to cytochrome c. We postulate that the mechanism of action of BHA could be by mimicking coenzyme-Q (ubiquinone).

A comparison of restrictive endonuclease sites of bovine herpesvirus type 1 isolates in Chile

The Frutillar 82, F nasal 90, F vaginal 90, Puente Alto 77, VMLB 79, and Bio Bio 92 isolates of bovine herpesvirus 1 (BHV-1) from Chile were analysed by Eco RI, Bam HI and Hind III restriction enzymes (RE). The Los Angeles (LA) strain was used as reference. The results indicated that the fingerprints of F nasal 90 and F vaginal 90 were identical to the three RE used, but they were different from the other isolates. Major differences were found for Puente Alto 77 and VMLB 79 isolates with Eco RI, and for Puente Alto 77 with Hind III compared with the other Chilean isolates. It is concluded that Chilean BHV-1 isolates obtained from diverse lesions and geographic locations are genomically different from each other and from the other strains described in the literature.

Effects of 2(3)-tert-butyl-4-hydroxyanisole (BHA) on in situ mitochondria of Trypanosoma cruzi

Results obtained with in situ mitochondria of Trypanosoma cruzi showed that this protozoon had only two energy coupling sites, sites II and III that correspond to higher eukaryote mitochondria. Rotenone did not inhibit the oxygen uptake of the parasite. These results suggest that the NADH-ubiquinone segment of the respiratory chain has no activity. Studies with in situ mitochondria confirmed that BHA, an antioxidant food additive, blocks the mitochondrial electron transport chain at the succinate-cytochrome b segment being the molecular basis of this trypanocidal action.

Peroxisomal organization in normal and cerebrohepatorenal (Zellweger) syndrome fibroblasts

The reported absence of morphologically detectable peroxisomes in liver and kidney tissue cells from patients affected by the autosomic recessive, inherited metabolic disease known as cerebrohepatorenal, or Zellweger, syndrome was studied in fibroblasts, assuming it to be a generalized defect. Normal cultured fibroblasts were shown to contain peroxisomes according to morphological, biochemical, and subcellular fractionation criteria: particle-bound catalase and fatty acyl-CoA oxidase copurify in subcellular fractionation by differential centrifugation or isopycnic equilibrium in continuous density gradients and peroxidase-positive organelles of approximately equal to 0.1 micron in diameter are detected in the cytoplasm. In Zellweger cultured fibroblasts, these peroxisomal enzymes are present; however, they behave as cytosolic enzymes in the different subcellular fractionation procedures employed and peroxisomes are not detected cytochemically. These findings support the hypothesis that the lack of peroxisomes in this genetic disease is the consequence of a defect in the assembly of the peroxisomal constituents. Furthermore, the value of fibroblasts for subcellular analysis of peroxisomal defects is illustrated.

Interaction between theophylline and oestrogen in the rat uterus

Theophylline alone or in the presence of 0.001, 0.01, 0.1 or 1 microgram oestradiol-17 beta/100 g body wt increase uterine RNA and protein content 6 h after administration. Uterine oedema induced by physiological doses of oestradiol-17 beta was increased further in the presence of theophylline. Theophylline decreased the number of eosinophils in the blood and concurrently decreased oestrogen-induced uterine oesinophilia at doses of 0.01, 0.1, 1, 10 or 30 micrograms oestradiol-17 beta/100 g body wt. Oestrogen binding by uterine eosinophils in vitro increased in the presence of theophylline. This effect of theophylline could explain the increase of oestrogen-induced uterine oedema in vivo.