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J D Rihs

Publications and source records attributed to J D Rihs.

33 records · Page 2Linked to original sources
PubMed1989

A pink-pigmented, oxidative, nonmotile bacterium as a cause of opportunistic infections.

We describe two cases of bacteremia due to a pink-pigmented, oxidative, nonmotile, gram-negative, rod-shaped organism. One case occurred in a febrile neutropenic patient and another in a chronically debilitated patient with pancreatic abscess. The first patient was cured with gentamicin and ticarcillin, but the second patient died while receiving cefamandole therapy. The organisms described here are similar to Methylobacterium mesophilicum (Pseudomonas mesophilica) and the "unnamed taxon" organisms. A major difference from M mesophilicum is the lack of methanol utilization. Further distinctions between our isolates and M mesophilicum are the lack of flagella in our organisms, growth at 42 degrees C, growth on MacConkey's agar, lack of acetamide assimilation, and citrate utilization. The lack of flagella is the principle difference between our isolates and those in the unnamed taxon. Both of the isolates were resistant to the cephalosporins, but susceptible to the aminoglycosides, ticarcillin-clavulanic acid, sulfamethoxazole and trimethoprim, and imipenem. With the growing population of immunocompromised and chronically ill patients, these organisms may emerge as important pathogens.

Abscess↗
PubMed1988

Acute cardiac tamponade due to cardiac actinomycosis.

Cardiac actinomycosis occurs in less than 2 percent of the patients with infections due to Actinomyces israelii. We describe the findings in a patient with acute cardiac tamponade who survived through pericardial drainage and aggressive medical therapy. Although uncommon, this disorder is important to recognize because it is curable with current medical and surgical therapy.

Actinomycosis↗
PubMed1986

Staphylococcus aureus nasal carriage and infection in patients on hemodialysis. Efficacy of antibiotic prophylaxis.

We conducted a five-year prospective controlled study of prophylaxis of Staphylococcus aureus nasal carriage and infection among patients in a hemodialysis unit. Carriers tended to have chronic colonization with a single phage type. S. aureus infections occurred significantly more frequently in carriers than in noncarriers and, in 93 percent of the infected carriers, were caused by the same phage type as that carried in the nares. Neither intravenous vancomycin nor topical bacitracin was found to be efficacious in eradicating nasal carriage. However, oral rifampin given for five days decreased S. aureus carriage over a one-month follow-up period, but within three months colonization of the nares recurred in most carriers, often with an S. aureus of the original phage type. Carriers were then randomly assigned to receive either rifampin or no prophylaxis. Rifampin was readministered at three-month intervals if culture of the anterior nares yielded S. aureus. Infections with S. aureus occurred significantly more frequently in carriers given no prophylaxis than in those given a full course of rifampin. S. aureus resistant to rifampin was isolated from the anterior nares of four patients, but these isolates were not implicated in any infections. The incidence of infection at the dialysis access site, skin, and soft tissue of patients on hemodialysis can be decreased by interventions directed at nasal carriage of S. aureus.

Administration, Intranasal↗
PubMed1986

A note on symbiosis of Legionella pneumophila and Tatlockia micdadei with human respiratory flora.

Sixteen micro-organisms, representing clinically important respiratory microflora, were tested for their ability to stimulate the growth of Legionella pneumophila and Tatlockia micdadei in nutritionally-deficient agar media. Nutritional symbiosis, indicated by the appearance of satellite colonies of L. pneumophila or T. micdadei, was observed for H. influenzae and N. meningitidis. This interaction between normal flora and pathogens of the respiratory tract may have clinical relevance in the pathogenesis of Legionnaires' disease and Pittsburgh pneumonia.

Bacterial Physiological Phenomena↗
PubMed1985

Isolation of Legionella pneumophila from blood with the BACTEC system: a prospective study yielding positive results.

In a prospective study of 16 patients with Legionnaires disease confirmed by cultural isolation of Legionella pneumophila from the respiratory tract, 38% (6 of 16) had positive blood cultures. Daily subcultures were made onto buffered charcoal-yeast extract plates from 6B aerobic and 7C anaerobic BACTEC blood culture bottles (Johnston Laboratories, Inc., Towson, Md.). Isolation of L. pneumophila was achieved from both aerobic and anaerobic bottles. L. pneumophila growth indices failed to exceed the BACTEC threshold limits; thus, the organism would have been overlooked despite its presence in the blood culture bottles. Bacteremic patients had statistically significant higher quantities of L. pneumophila isolated from sputum and visualized on direct fluorescent antibody stains. Thus, the potential exists for improved diagnosis of Legionella infection by a relatively noninvasive procedure (blood culture) with an instrument already in use in many hospital laboratories.

Aerobiosis↗
PubMed1984

A pseudo-outbreak of Streptomyces infections linked to laboratory construction.

Over a four-week period, nine isolates of Streptomyces species were identified from seven blood cultures, one infected gortex graft, and one cerebrospinal fluid (CSF) specimen. None of the patients were clinically infected or received antimicrobial therapy. Blood culture collecting tubes, iodoform prep solutions, BAC-TEC filters, and alcohol prep pads were cultured but did not reveal a source of contamination. Six additional clinical specimens became positive, and the occurrence of construction in the laboratory was considered as a source of the contaminating organism. Blood agar plates were placed for 20 minutes in an area undergoing construction. Streptomyces grew in heavy concentrations on nine of ten plates in the construction site, but only one colony on ten plates grew from a hallway not undergoing construction. Isolation of the organism ceased with cessation of the construction. The authors conclude that the Streptomyces pseudo-outbreak was related to construction around the laboratory, with probable airborne contamination of clinical specimens.

Air Microbiology↗
PubMed1983

Diagnosis of Legionnaires' disease. An update of laboratory methods with new emphasis on isolation by culture.

A prospective clinical study of 40 cases of legionnaires' disease combined with serial laboratory examinations enabled us to present an update as well as new recommendations concerning the use of diagnostic tests for legionnaires' disease. Transtracheal aspirate specimens are the optimal specimen for recovery of Legionella pneumophila by culture as well as the most sensitive method for early diagnosis. In addition, with recent improvements in culture media and methodology, L pneumophila can now be readily isolated from sputum. Examination of respiratory specimens by direct immunofluorescence (DFA) is useful, but the sensitivity is much less than that of culture. The yield from DFA examination directly correlates with the number of L pneumophila recoverable by cultural methods; thus, the DFA test result may be negative in an early or mild case of legionnaires' disease. Antibody titers were elevated in 27% of cases within one week of onset of pneumonia and may, therefore, be useful in early diagnosis in selected patients.

Antibodies, Bacterial↗
PubMed1983

Legionella pneumophila contamination of a hospital humidifier. Demonstration of aerosol transmission and subsequent subclinical infection in exposed guinea pigs.

Water from a humidifier located in the hospital was found to be contaminated with Legionella pneumophila, serogroup 1. The source of water for the humidifier was the hospital potable water system. Exposure of culture mediums to the humidifier aerosols yielded L. pneumophila, serogroup 1. Exposure of guinea pigs to humidifier aerosols produced a subclinical infection as demonstrated by seroconversion to L. pneumophila. Seroconversion rate of guinea pigs to L. pneumophila was higher when greater quantities of L. pneumophila were present in the water; a corresponding increase in recovery of the organism from culture mediums exposed to aerosols was also seen. This report shows that mechanically created aerosols of Legionella-contaminated potable water might be the vehicle of transmission of Legionnaires' disease, especially in the hospital setting.

Aerosols↗
PubMed1983

Pseudomonas stutzeri bacteremia associated with hemodialysis.

Pseudomonas stutzeri bacteremia developed in six patients undergoing hemodialysis. Fever, shaking chills, nausea, and vomiting were observed. All patients recovered, although only two received specific antibiotic therapy. The infections occurred sporadically over a period of nine months. Pseudomonas stutzeri was subsequently isolated from the dialysate that circulates within the hemodialysis machine. The ultimate source was the deionized water that is combined with the liquid concentrate to form the dialysate. Pseudomonas stutzeri could be localized to the top cannister of the dialysis machine but was also isolated throughout the machine, including the bottom reservoir and the recirculating pump. The emphasis on handwashing, strict compliance with disinfection procedures, and elimination of prolonged sitting times for the filled machine after disinfection resulted in no further cases of P stutzeri infection.

Humans↗
PubMed1974

Medium containing trypan blue and antibiotics for the detection of Cryptococcus neoformans in clinical samples.

A medium containing trypan blue, gentamicin, and chloramphenicol is introduced for the detection of Cryptococcus neoformans and Cryptococcus species from clinical samples. Ten recently isolated strains of Cryptococcus species as well as several clinical isolates of C. neoformans incorporated trypan blue and produced dark blue colonies on this mycological medium, whereas other common yeasts were light blue. The laboratory diagnosis of two cases of cryptococcosis was accomplished by the isolation of C. neoformans on the antibiotic-dye-containing medium. Compared to conventional media supporting large numbers of Pseudomonas aeruginosa and other gram-negative bacilli, the new medium was selective for yeasts. In one instance, the colonization of the respiratory tract by C. neoformans which led to fungemia was traced by the use of the antibiotic-dye medium. The antibiotic mixture, utilized herein, was more effective in suppressing bacteria contained in samples from patients than a medium containing cycloheximide and chloramphenicol.

Candida albicans↗
PubMedDate not supplied

Community-acquired pneumonia caused by Legionella dumoffii in a patient with hairy cell leukemia.

A case of community-acquired pneumonia caused by Legionella dumoffii in a patient with hairy cell leukemia is described. Diagnosis was confirmed by isolation by culture of sputum and broncho-alveolar lavage specimens, positive direct fluorescent antibody stains, and antibody seroconversion from 1:16 (acute) to 1:4096 (six months). The blue white autofluorescence of the L. dumoffii colonies when viewed under ultraviolet light was particularly useful in preliminary identification. The patient recovered from his pneumonia after administration of erythromycin and rifampin. Legionella have been shown to multiply in monocytes and cell-mediated immunity appears to be the primary mechanism of host defense in man. Hairy cell leukemia is characterized by monocyte dysfunction and such patients have a predilection for infection by microbes that are controlled by cell-mediated defenses. We review other cases of community-acquired L. dumoffii pneumonia as well as other cases of Legionella infection in patients with hairy cell leukemia.

Antibodies, Bacterial↗
PubMedDate not supplied

Evaluation of housestaff physicians' preparation and interpretation of sputum Gram stains for community-acquired pneumonia.

OBJECTIVE: To evaluate the preparation and interpretation of sputum Gram stains by housestaff physicians in the assessment of patients with community-acquired pneumonia. DESIGN: A prospective, multicenter study. SETTING: Two university-affiliated hospitals in Pittsburgh. PATIENTS: Ninety-nine cases of clinically and radiographically established pneumonia occurring in 97 patients. Diagnostic test assessment: Housestaff and microbiology personnel prepared a Gram stain for each case of pneumonia. Housestaff assessed the presence and identity of a predominant microbial organism on the slides they prepared. Two senior staff microbiologists, blinded to patient and preparer, evaluated all slides for preparation, sputum purulence, and identification of the predominant organism. Two reference standards were used to assess the sensitivity, specificity, and predictive values of housestaff's Gram-stain interpretations: 1) senior staff microbiologists' determinations of the microbes present using the slides without benefit of culture results, and 2) the etiologic agent derived from results of sputum culture, blood culture, or serology. MEASUREMENTS AND MAIN RESULTS: Housestaff physicians completed a Gram stain in 58% of the pneumonia episodes. Gram stains were not made in 42% of cases, primarily because patients were unable to produce sputum. Fifteen percent of housestaff's smears were judged inadequately prepared, compared with 3% for the laboratory personnel (p less than 0.01). Housestaff obtained purulent sputum samples significantly more often than did nursing personnel (58% versus 38%; p less than 0.01). Housestaff's Gram stains were 90% sensitive for detecting pneumococcus, with a 50% false-positive rate. The sensitivity of the Gram stain was less for identification of Haemophilus influenzae than for identification of Streptococcus pneumoniae. A single antimicrobial agent was chosen as initial therapy for 50% of the patients in whom housestaff identified a predominant organism, compared with 30% in whom a predominant organism was not identified (p less than or equal to 0.05). CONCLUSIONS: Although housestaff obtained purulent sputum samples more frequently than did nursing personnel, they made systematic errors in the preparation and interpretation of Gram-stained slides. Housestaff physicians should receive formal training in the preparation and interpretation of Gram stains; the specific defects elucidated in this study warrant special attention.

Adolescent↗
PubMedDate not supplied

Recurrent methicillin-resistant Staphylococcus aureus osteomyelitis: combination antibiotic therapy with evaluation by serum bactericidal titers.

OBJECTIVE: To report on a patient with recurrent methicillin-resistant Staphylococcus aureus (MRSA) osteomyelitis and bacteremia successfully treated with combination antibiotic therapy. CASE SUMMARY: Two sets of blood cultures from a 55-year-old man with fever, malaise, and low back pain grew MRSA. Radiologic studies of the spine showed bony changes consistent with osteomyelitis. Soon after completing 6 weeks of vancomycin, the patient experienced a recurrence of back pain. Laboratory values included an increase in the sedimentation rate to 53 mm/h and positive blood cultures for MRSA. Vancomycin, gentamicin, and rifampin were administered for 8 weeks. Serum inhibitory and bactericidal titers were more than 1:1024 for both the peak and trough concentrations. Radiologic studies of the spine showed healing osteomyelitis. Two years after completion of antibiotic therapy, the infection has not recurred. DISCUSSION: Antibiotic therapy alone was attempted because the patient was considered a risky surgical candidate. Serum inhibitory and bactericidal titers documented the high in vivo activity of the vancomycin, gentamicin, and rifampin combination. Initiation of vancomycin, gentamicin, and rifampin combination. Initiation of vancomycin therapy led to disappearance of the fever and back pain. Cure was documented by sustained normalization of the erythrocyte sedimentation rate and radiologic evidence of healing. CONCLUSIONS: Combination antibiotic therapy with vancomycin, rifampin, and low-dose gentamicin (1 mg/kg q12h) may be useful for deep-seated tissue infection caused by MRSA.

Anti-Bacterial Agents↗
PubMedDate not supplied

Antimicrobial susceptibility patterns of the Bacteroides fragilis group in the United States, 1989.

A national survey of Bacteroides fragilis group was continued in 1989 for the ninth consecutive year. Seven hundred thirty-nine isolates of B fragilis group from eight centers were tested for susceptibility to 14 antimicrobials. Sulbactam and clavulanic acid, beta-lactamase inhibitors, were tested at a constant concentration of 8 micrograms/ml and 2 micrograms/ml, respectively. Sulbactam was also tested in a fixed ratio of 1:2. Imipenem, ampicillin+sulbactam, and ticarcillin+clavulanic acid had resistance of less than 1% at breakpoints of 8 micrograms/ml, 16 micrograms/ml, and 64 micrograms/ml, respectively. At 32 micrograms/ml, resistance to cefoxitin, cefotetan, ceftizoxime, and ceftriaxone were 4%, 25%, 26%, and 46%, respectively. Clindamycin resistance was 10% at a breakpoint of 4 micrograms/ml. No isolates were resistant to chloramphenicol or metronidazole. Resistance for five B fragilis species to cefoxitin, ceftizoxime, and cefotetan varied greatly among both species and participating institutions. The addition of a beta-lactamase inhibitor increased the potency of the beta-lactam drugs tested as combinations. This finding suggests that beta-lactamase production is the major resistance factor in members of the B fragilis group.

Anti-Bacterial Agents↗