Antibody testing in Indian children with celiac disease.

BACKGROUND: We prospectively evaluated the usefulness of IgA tissue transglutaminase antibodies (IgA tTG) in the initial diagnosis of celiac disease (CD) and compared its diagnostic potential with that of IgA anti-endomysial antibodies (IgA EMA) and anti-IgA and IgG gliadin antibodies (AGA and AGG, respectively). METHODS: Sera of 23 untreated children fulfilling the revised ESPGHAN criteria for diagnosis of CD (Group I; mean age 10.8 y); 19 disease controls (Group II; mean age 8.5 y) presenting with chronic diarrhea, short stature or both; and 22 healthy children (Group III; mean age 8.8 y) were studied. These were tested in a blinded manner for AGA, AGG, IgA tTG (guinea pig as antigen) and IgA EMA. RESULTS: In Group I, IgA EMA was positive in 19, IgA tTG in 17, AGA in 14 and AGG in 17 patients. In Group II, these tests were positive in 1, 0, 2 and 14 patients, respectively and in Group III, in 0, 0, 0 and 1 child, respectively. Analyzing data from Group I and II, IgA EMA, IgA tTG, AGA and AGG had sensitivity rates of 83%, 74%, 61% and 74%, respectively; the specificity rates were 95%, 100%, 89% and 26%; positive predictive values were 95%, 100%, 88% and 55% and negative predictive values were 82%, 74%, 65% and 45%, respectively. CONCLUSION: IgA tTG is useful for the diagnosis of CD, with sensitivity and specificity rates comparable to those of EMA and this test is well suited for use in tropical countries like India.     

Dengue fever presenting with acute colitis.

Gastrointestinal manifestations of dengue fever are mainly in the form of bleeding or liver function abnormalities. Dengue fever presenting as acute colitis-like picture is not reported to date. We report a 50-year-old man with dengue fever presenting with lower gastrointestinal bleeding and colonoscopic features of acute inflammatory colitis.     

Preemptive Retransplantation for BK Virus Nephropathy: Successful Outcome Despite Active Viremia

BK virus nephropathy (BKVN) is now recognized as a major cause of renal allograft loss. Recent reports suggest that retransplantation in patients with graft loss due to BKVN is safe after return to dialysis. Since early transplantation is associated with improved outcomes, it would be advantageous if this procedure could be performed prior to ultimate graft loss. However, little data are available regarding the safety of this approach during active viremia. In this report, we describe successful preemptive retransplantation with simultaneous allograft nephrectomy in two patients with active BKVN and viremia at the time of surgery. With 21- and 12-month follow-up, respectively, both patients have stable allograft function and no evidence for active viral replication. We conclude that preemptive retransplantation can be considered in patients with failing allografts due to BKVN.     

An unusual presentation of a recurrent neurofibroma in the hand

Neurofibromas in the hand are uncommon and constitute less than 5% of all hand tumours. Accurate diagnosis and appropriate management are important because malignant transformation has been reported, especially in Von Recklinghausen’s neurofibromatosis. We report a case of a large neurofibroma in the right hand of an 18-year-old girl of Afro-Caribbean origin. She was symptomatic with complaints of pain and weakness of grip. General examination revealed multiple café-au-lait spots on the trunk and one nodular swelling in the forearm. The swelling was excised through a palmar approach and histology proved it to be a neurofibroma. The case is being reported for its rarity and it emphasizes the importance of general examination. Histopathological examination is vital in excluding malignant transformation.     

Use of fluorometry in assessing the efficacy of a cation-sensitive gel as an ophthalmic vehicle: comparison with scintigraphy.

Gelrite, a heteropolysaccharide that forms a gel in the presence of cations, was tested in humans for its efficacy as an ophthalmic vehicle by a nonivasive fluorometric technique. Fluorescein was used as the tracer, and its concentration in the anterior chamber was used as the principal measure of bioavailability. The gel afforded a twofold increase in penetration of fluorescein compared with an isotonic buffer solution; this increase is slightly more than can be obtained with simple viscous vehicles. The increase in penetration caused by Gelrite was confirmed by measurements of the contact time of fluorescein in the tear film with the cornea. Earlier experiments with scintigraphy suggested a considerably greater contact time of fluorescein with the cornea when Gelrite was used. However, this increased contact time may be because the technique also measures radioactive tracer that had dried out on the lid margins. Accordingly, significant quantities of fluorescein could be eluted from the lids after the penetration experiments were completed.     

The Role of Sialic Acid in Opsonin-Dependent and Opsonin-Independent Adhesion of Listeria monocytogenes to Murine Peritoneal Macrophages

The adhesion of listeriae to host cells employs mechanisms which are complex and not well understood. Listeria monocytogenes is a facultative intracellular pathogen responsible for meningoencephalitis, septicemia, and abortion in susceptible and immunocompromised individuals. Subsequent to colonization and penetration of the gut epithelium, the organism attaches to resident macrophages and replicates intracellularly, thus evading the humoral immune system of the infected host. The focus of these studies was to investigate the attachment of the organism to murine peritoneal macrophages in an opsonin-dependent and opsonin-independent fashion. Assessment of competitive binding experiments by immunofluorescence and enzyme-linked immunosorbent assays showed that adhesion of the organism to macrophages in the presence or absence of opsonins was inhibited (90%) by N-acetylneuraminic acid (NAcNeu). In addition, the lectin from Maackia amurensis, with affinity for NAcNeu-α(2,3)galactose, blocked binding of L. monocytogenes to host cells. Oxidation of the surface carbohydrates on the organism by using sodium metaperiodate resulted in a dose-dependent reduction (up to 98%) in adherence to macrophages. Monoclonal antibody to complement receptor 3 did not prevent listeriae from binding to mouse macrophages or from replicating within the infected cells whether or not normal mouse serum was present. Based on our results, we propose the involvement of NAcNeu, a member of the sialic acid group, in the attachment of L. monocytogenes to permissive murine macrophages.