Prevalence of Cryptosporidium parvum infection in children along the Texas-Mexico border and associated risk factors.

We examined the epidemiology of Cryptosporidium parvum in children aged 6 months to 13 years living in 1) colonias along the border (n = 105), 2) a clinic in an urban border community (n = 65), and 3) clinics in a large urban nonborder area (n = 109). Serum IgG and IgA anticryptosporidial antibodies were measured by enzyme-linked immunosorbent assay (ELISA). Overall, 70.

Experimental cryptosporidiosis in adult and neonatal rabbits.

Neonatal and adult New Zealand White rabbits were infected experimentally with Cryptosporidium parvum. No histologic evidence of infection was found in adult rabbits. However, increased levels of anti-cryptosporidial serum IgG were present, and multiple antigens were detected by serum on immunoblots.

Protozoal colonization of the intestinal tract in institutionalized Romanian children.

To determine the prevalence of intestinal parasitic infections in 92 Romanian children institutionalized at Colentina Hospital (Bucharest, Romania) and at the Dystrophic Center (Vidra, Romania), medical charts were reviewed and complete physical examinations were performed. The nutritional status of each child was evaluated, and their sera were tested for the presence of antibodies to human immunodeficiency virus (HIV) and Cryptosporidium. Fecal samples were collected in 10% formalin and examined by an immunofluorescent assay and by trichrome staining for intestinal parasites.

A Cryptosporidium parvum genomic region encoding hemolytic activity.

Successful parasitization by Cryptosporidium parvum requires multiple disruptions in both host and protozoan cell membranes as cryptosporidial sporozoites invade intestinal epithelial cells and subsequently develop into asexual and sexual life stages. To identify cryptosporidial proteins which may play a role in these membrane alterations, hemolytic activity was used as a marker to screen a C. parvum genomic expression library.

Frequency of unrecognized Bordetella pertussis infections in adults.

To investigate the frequency of unrecognized Bordetella pertussis infections in adults, we performed IgA and IgG ELISA antibody studies with four B. pertussis antigens--i.e.

Enteral human serum immunoglobulin treatment of cryptosporidiosis in mice with severe combined immunodeficiency.

The anti-cryptosporidial immunoglobulin G antibodies in two commercially available human serum immunoglobulin (HSIG) products were quantified and characterized. The mean level of Cryptosporidium parvum-specific immunoglobulin G in HSIG was eightfold higher than the antibody level found in the sera of three immunocompetent individuals convalescing from cryptosporidiosis. However, HSIG products displayed no reactivity to cryptosporidial antigens in immunoblot analyses, while convalescent-phase sera demonstrated characteristic banding patterns.

Inability of interferon-gamma and aminoguanidine to alter Cryptosporidium parvum infection in mice with severe combined immunodeficiency.

Severe combined immunodeficiency (scid) mice have been useful in identifying specific host defense systems responsible for containing and eradicating Cryptosporidium parvum infection. Adult scid mice were given C. parvum oocysts and treated weekly with monoclonal antimurine interferon-gamma (anti-IFN-gamma).

Rhodococcus equi infections of humans. 12 cases and a review of the literature.

Increased recognition of Rhodococcus equi as a human pathogen has occurred since 1983, when the first review article summarized the world's literature of 12 cases. In this article, we present 12 cases from the University of Oklahoma Health Sciences Center and review 60 from the literature. Most cases occur in immunocompromised hosts and present as chronic cavitary pneumonias.

Seroprevalence of cryptosporidial antibodies during infancy, childhood, and adolescence.

Cryptosporidium parvum causes mild to moderately severe diarrhea in immunocompetent individuals. Cryptosporidial antibodies in the sera of 803 children seen at Children's Hospital of Oklahoma were measured by means of an ELISA. Thirteen percent of children younger than 5 years of age were seropositive for antibodies to C.

Effect of abrogation of natural killer cell activity on the course of candidiasis induced by intraperitoneal administration and gastrointestinal candidiasis in mice with severe combined immunodeficiency.

Candida albicans CFU per gram of tissue recovered from livers, spleens, and kidneys of 12 severe combined immunodeficiency (scid) and 12 BALB/c mice 5 days after intraperitoneal (i.p.) administration of 10(7) C.

Cryptosporidium parvum infection after abrogation of natural killer cell activity in normal and severe combined immunodeficiency mice.

The role of natural killer (NK) cell activity in adult mice with severe combined immunodeficiency (scid mice) infected with Cryptosporidium parvum oocytes was evaluated. Adult BALB/c and scid mice were inoculated intragastrically with 10(6) C. parvum oocysts after the administration of anti-asialo-GM1 or control normal rabbit serum.

Septicemia and meningitis caused by Helicobacter cinaedi in a neonate.

Helicobacter cinaedi has been most frequently isolated from rectal swabs of homosexual men with proctocolitis. The microorganism is a normal intestinal inhabitant of hamsters. We report a case of septicemia and meningitis by H.

Bovine humoral immune response to Cryptosporidium parvum.

Cryptosporidiosis is a diarrheal disease predominantly affecting cattle and humans. Sera from experimentally infected calves and calves of various ages with no histories of exposure were evaluated for immunoglobulin G to Cryptosporidium parvum. An age-associated increase in immunoglobulin G was present in experimental calves and in calves with no histories of infection from 1 to 3, but not > 3, months of age.

Severe mycoplasma pneumonia in young children with Down syndrome.

Three young children with Down syndrome developed fever, cough, wheezing, irritability, and tachypnea. They had bilateral infiltrates on their chest radiographs and developed respiratory distress, which required their hospitalization. Laboratory studies suggested that the children had mycoplasma pneumonia.

Cryptosporidiosis in adult and neonatal mice with severe combined immunodeficiency.

Cryptosporidium parvum causes protracted diarrhoea in immunodeficient hosts. To characterize the role that T and B lymphocytes play in the eradication of the parasite from the intestinal mucosa, the course of infection in mice with severe combined immunodeficiency (SCID) was studied. Twenty-nine SCID and 26 BALB/c adult mice received 10(6) oocysts intragastrically.

Relapsing pneumococcal bacteremia in immunocompromised patients.

Relapse of Streptococcus pneumoniae bacteremia after appropriate therapy is thought to be rare, even in immunocompromised patients. We describe three immunodeficient patients who experienced repeated episodes of pneumococcal bacteremia within 8 weeks after receiving appropriate therapy. Serotyping and DNA fingerprinting of respective isolates strongly suggested that each patient's bacteremic relapse was caused by the same pneumococcal strain.

Effects of carbohydrates and lectins on cryptosporidial sporozoite penetration of cultured cell monolayers.

Cryptosporidium parvum first interacts with enterocytes when sporozoites penetrate the host plasma membrane. We have developed a shell vial assay using human embryonic Intestine 407 cells and purified C. parvum sporozoites to study this process.

Pneumonia caused by a newly recognized pseudomonad in a child with chronic granulomatous disease.

A pseudomonad was isolated from the pleural fluid and pulmonary decortication tissue of a 5-year-old child with chronic granulomatous disease. Although the isolate was phenotypically similar to Pseudomonas cepacia, its biochemical profile was more similar to that of Pseudomonas pickettii biovar 2. Its slow growth rate, ability to hydrolyze urea rapidly, and lateral and polar flagellar pattern were suggestive of Oligella ureolytica (formerly CDC group IVe).