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H W Wilkinson

Publications and source records attributed to H W Wilkinson.

60 records · Page 4Linked to original sources

Distribution by serological type of group B streptococci isolated from a variety of clinical material over a five-year period (with special reference to neonatal sepsis and meningitis).

A total of 898 group B streptococci isolated from a wide variety of human clinical sources from July 1967 through June 1972 were typed by the Lancefield precipitin test. Only 11% of the strains were nontypable. Twenty-six percent of the group B strains were from respiratory sources, 22% were from cerebrospinal fluid (CSF) and blood, 13% were from the female genital tract, 12% were urine specimens, and the remaining 27% were from other varied sources. The clinical conditions reported for patients from whom these organisms were isolated included neonatal meningitis and sepsis, pharyngitis, urinary tract and female genital tract infections, and various skin and wound infections. Seventy percent of the CSF and blood cultures from patients with meningitis or sepsis, or both, were type III, whereas the overall percentage of this type was 32%. All but three CSF isolates were from patients under 2 years of age; the distribution of CSF isolates appeared to be the same for both sexes. In contrast, group B streptococci were isolated more frequently from the blood of males than from the blood of females. There were twice as many blood cultures from patients under 2 years of age than from those that were older.

Adolescent↗

Comparison of streptococcal R antigens.

At least four distinct nonspecific protein R antigens were found in streptococci of groups A, B, and C by immunodiffusion in agar gel with anti-R sera.

Antigens, Bacterial↗

Type-specific antigens of group B type Ic streptococci.

The type-specific antigens of group B type Ic (old designation type Ii) streptococci were extracted, purified, and characterized by serological and chemical methods. The Ia antigen, shared by types Ia and Ic, is a polysaccharide composed of 69% galactose and 25% glucosamine (i.e., 31% N-acetyl-glucosamine). However, these monosaccharides failed to inhibit significantly the quantitative precipitin reactions between purified antigen and type Ia antiserum. Indications are that the immunodominant group of this antigen consists of more than a simple monosaccharide. The Ic antigen, shared by types Ib and Ic, is a protein unrelated to the X and R protein antigens. Ic antigen consists of two serologically active determinants, one of which is susceptible to both trypsin and pepsin digestion and the other to pepsin but not to trypsin digestion. Acrylamide gel electrophoresis of the partially purified Ic antigen resulted in the occurrence of both determinants throughout the length of the gel, as shown by double gel diffusion slides.

Animals↗

Serological relationships of type I antigens of group B streptococci.

Some of the complex antigenic relationships of type I group B streptococci from various clinical sources were defined by means of immunodiffusion, absorption, and precipitin tests. Three predominant types are described: Ia, Ib, and Ii. Methods for preparing antisera for differentiating type I strains are presented.

Absorption↗

Legionella moravica sp. nov. and Legionella brunensis sp. nov. isolated from cooling-tower water.

Two Legionella-like organisms were isolated from cooling-tower water samples in Czechoslovakia. They were presumptively identified as legionellae by their growth on buffered charcoal-yeast extract agar (BCYE) containing L-cysteine and their absence of growth on BCYE without L-cysteine. Both strains contained predominately branch-chained cellular fatty acids and were therefore definitively placed in the genus Legionella. They were serologically distinct from other described Legionella species and were shown by DNA studies to constitute two new Legionella species, Legionella moravica (type strain 316-36; ATCC 43877) and Legionella brunensis (type strain 441-1; ATCC 43878).

Czechoslovakia↗

Immunodiagnostic tests for Lyme disease.

Standardized serologic tests for Lyme disease are needed, as isolation or in situ demonstration of the spirochete has proved difficult. At the Centers for Disease Control (CDC), an indirect immunofluorescence assay (IFA) was modified from a previously described IFA, and an enzyme-linked immunosorbent assay (ELISA) was developed with soluble spirochetal antigens. Both tests were evaluated with sera from Lyme disease patients, normal controls, and patients with other diseases. They were highly specific for Lyme disease when sera from patients with syphilis were excluded. Sensitivity varied with disease stage: for patients with erythema chronicum migrans alone, the IFA was 53 percent sensitive and the ELISA was 67 percent sensitive. In contrast, all patients with complicated Lyme disease had at least one serum specimen positive in both tests. Twenty-six percent of the sera from 289 patients with suspected Lyme disease that were submitted to CDC in 1983 had IFA titers greater than or equal to 256 and thus were considered positive. Both tests should be useful diagnostic and epidemiologic aids.

Antibodies, Bacterial↗