Biomedical subjects

S A Harding

Publications and source records attributed to S A Harding.

10 recordsLinked to original sources

PubMed1979

Opportunistic pneumonia: a clinicopathological study of five cases caused by an unidentified acid-fast bacterium.

Five patients had opportunistic pulmonary infection caused by acid-fast bacilli, unusual clinical presentations and a unique pathological picture. Clinically, these cases mimicked septic pulmonary emboli or bacterial pneumonia. The infection was temporally related to high-dose corticosteroid therapy, given for renal-transplant rejection in four patients and for therapy of lymphocytic lymphoma in one. Histologic sections of lung-biopsy or autopsy material showed an acute suppurative pneumonia with dense alveolar infiltration by neutrophils, without granuloma formation or caseous necrosis. Predominantly intracellular acid-fast bacilli were present. The organism failed to grow in culture on routine bacterial, fungal and mycobacterial mediums. This unusual and possibly new acid-fast organism is a probable cause of suppurative pneumonia in impaired hosts receiving corticosteroid therapy.

Adrenal Cortex Hormones↗

PubMed1979

Pulmonary infection with capsule-deficient cryptococcus neoformans.

A case of bilateral lobar pneumonia due to Crytococcus neoformans is presented. The capsule-deficient fungal organisms within tissue were suggestive of Histoplasma capsulatum. Cultures grew Cryptococcus neoformans and there was cryptococcal antigen in the serum. Pulmonary cryptococcosis and the occurrence of unencapsulated cryptococci are reviewed. The important role both culture and the latex agglutination test for cryptococcal antigen play in the differential diagnosis of systemic fungal infections with over-lapping histopathology are discussed.

Adult↗

PubMed1979

Simultaneous disseminated aspergillosis and zygomycosis in a leukemic patient.

Although the incidence of fungal infections is increasing, infections caused by more than one fungus are rare. We have described the clinical, pathologic, and mycologic findings in a leukemic patient with simultaneous pulmonary infection and systemic dissemination caused by Aspergillus fumigatus and Rhizopus sp.

Adult↗

PubMed1979

Enzyme-linked immunosorbent assay for detection of Streptococcus pneumoniae antigen.

An enzyme-linked immunosorbent assay (ELISA) was developed for the detection of Streptococcus pneumoniae polysaccharide antigen in cerebrospinal fluid and serum. Sensitivity and specificity were determined for purified antigen preparations. Specificity was also evaluated in the rabbit meningitis model, and the sensitivity was compared to counterimmunoelectrophoresis, using the infected rabbits' cerebrospinal fluid and serum. The ELISA was a specific technique for detecting S. pneumoniae antigen. ELISA was 25 times more sensitive than counterimmunoelectrophoresis for purified antigen and resulted in an increased positivity of the cerebrospinal fluid and serum from infected rabbits. ELISA should prove very useful in the diagnosis of pneumococcal infections.

Animals↗

PubMed1979

Evaluation and comparison of two assays for detection of immunity to rubella infection.

Two commercially available rapid screening tests, Rubacell (Abbott Laboratories; passive hemagglutination) and FIAX (International Diagnostic Technology; indirect immunofluorescence) were compared with a standard hemagglutination inhibition assay for detection of immunity to rubella infection. In tests of approximately 300 sera, both rapid assays were specific and sensitive and showed a high predictive value of a positive result. Within-run reproducibility studies were excellent for both tests; however, Rubacell was superior to FIAX with respect to time-cost analysis.

Antibodies, Viral↗

PubMed1979

Cystic chromomycosis due to Wangiella dermatitidis.

Chromomycosis is a chronic, slowly progressive disease of the skin and subcutaneous tissue produced by several species of dematiaceous or pigmented fungi, especially Phialophora gougeroti. Verrucous nodules and flattened annular plaques are the most frequently reported skin lesions in chromomycosis, but deep abscesses and cystic lesions have also been reported. We describe herein a case of cystic chromomycosis due to Wangiella dermatitidis that developed following a nonprenetrating injury to the thumb.

Chromoblastomycosis↗

PubMed1976

Three serologic tests for candidiasis. Diagnostic value in distinguishing deep or disseminated infection from superficial infection or colonization.

One hundred fifty-one sera from 100 hospitalized patients with positive cultures for yeasts were assayed using whole-cell agglutination (Aggl.), agar gel diffusion (AGD), and counterimmunoelectrophoresis (CEP) to determine the relative diagnostic values of three serologic tests for anti-Candida antibodies. Serial samples were obtained from 29 patients. Tests were read blindly; correlations of the three test results with culture results and clinical findings were determined only after all data had been accumulated. Thirty-five of 100 patients had Aggl. titers of 1:160 or greater, although 13/35 had no evidence of deep or disseminated disease. Twenty-four of 100 patients had clinical or autopsy evidence of deep or disseminated candidiasis; 22/24 had Aggl. titers of 1:160 or greater. Twenty of the 24 patients were CEP-positive, whereas 18/24 were AGD-positive. In five patients CEP became positive earlier (10--21 days) than AGD. Three patients had false-positive precipitin tests, two by both CEP and AGD and the third by CEP only. In this population, a positive CEP and a positive AGD test showed good correlation with deep or disseminated candidiasis, whereas a negatvie Aggl. test showed the best correlation for excluding deep or systemic candidiasis.

Agglutination Tests↗

PubMed1976

Gas-chromatographic determination of 5-fluorocytosine in human serum.

We describe a sensitive and precise gas-chromatographic method, in which cytosine is used as the internal standard, for determination of an antifungal agent, 5-fluorocytosine, in serum. The trimethylsilyl derivative of this drug is well separated from the internal standard and from normal serum constituents. Amphotericin B does not interfere with the determination of 5-fluorocytosine. The lower limit of detection for 5-fluorocytosine is 1 mg/liter when 200 mul of serum is analyzed. Within-run precision (CV), established by analysis of 10 replicates, was 4.5% at a concentration of 19.9 mg/liter. Twenty-five serum samples were analyzed for 5-fluorocytosine by a microbiological assay and by the gas-chromatographic method. Mean value observed with the bioassay was 78.5 mg/liter and with our procedure was 69.4 mg/liter. When values for our assay were regressed against values for the bioassay, slope of the least-squares line was 0.85, intercept was 2.7 mg/liter, and r was 0.93.

Chromatography, Gas↗

PubMed1975

Evaluation of antibody coating of yeasts in urine as an indicator of the site of urinary tract infection.

Antibody coating of yeasts (Candida sp. and Torulopsis sp.) found in urine specimens was investigated to ascertain whether the presence of such coating might identify the site of urinary tract infection. Washed yeast cells obtained by centrifugation of fresh urine specimens were reacted with fluorescein-conjugated goat antihuman immunoglobulins (Ig) G, A, and M and examined by fluorescent microscopy. IgG was found on the surface of all species of yeast encountered in all urine specimens evaluted, whereas there was variability of IgA AND IgM coating. Antibody coating with IgG, IgA, AND IgM was also demonstrated on yeasts from other body sites (sputum, gastrostomy, oral, etc.). Control experiments confirmed the specificity of the reactions. Thus, it appears that yeasts from any body site are coated with antibodies. These results are in contrast to recent work with bacteria which showed that the presence of antibody-coated (IgG) bacteria indicates upper urinary tract infection (pyelonephritis) while bacteria are not coated with antibodies in lower urinary tract infection. Since all yeasts from all body sites tested were found to be coated with antibody regardless of the clinical situation, the presence of surface antibody has no diagnostic value in identifying the site of urinary tract infection with yeasts.

Antibodies, Fungal↗

PubMed1975

Platelet support for cardiopulmonary bypass surgery.

After we discontinued the use of fresh blood for cardiopulmonary bypass surgery, we routinely provided platelet concentrates for the patients. To ascertain if this was necessary, patients paired for procedure and age were given either 4 units of platelets (Group I) or no platelets (Group II). Platelet counts were obtained preoperatively; hourly during bypass; immediately, 1/2 hour, and 3 to 4 hours after bypass; and daily for 7 postoperative days. In the 60 patients evaluated, a significant difference between mean platelet counts could not be demonstrated at any time. Total blood use and the total time required for postbypass hemostasis was not significantly different between the two groups. The degree of thrombocytopenia could not be correlated by bypass time. Platelet concentrates or fresh blood are not needed prophylactically for cardiopulmonary bypass surgery, and their usage should be reserved for the occasional patient who manifests thrombocytopenia as well as hemorrhagic complications.

Adolescent↗