Biomedical subjects

G J Zenon

Publications and source records attributed to G J Zenon.

7 recordsLinked to original sources

PubMed1995

An outbreak of Burkholderia (formerly Pseudomonas) cepacia respiratory tract colonization and infection associated with nebulized albuterol therapy.

OBJECTIVE: To investigate an outbreak of Burkholderia (formerly Pseudomonas) cepacia respiratory tract colonization and infection in mechanically ventilated patients. DESIGN: A retrospective case-control and bacteriologic study. SETTING: Veterans Affairs medical center. PATIENTS: 42 mechanically ventilated patients who developed respiratory tract colonization or infection with B. cepacia and 135 ventilator-dependent controls who were not colonized and did not develop infections. MEASUREMENTS: Clinical and demographic data; benzalkonium chloride concentrations and pH levels in albuterol sulfate solutions; repetitive-element polymerase chain reaction (PCR)-mediated molecular fingerprinting on eight patient isolates and three environmental B. cepacia isolates that were available for study. RESULTS: 42 patients had B. cepacia respiratory tract colonization or infection. Observation of intensive care unit and respiratory care personnel showed faulty infection control procedures (for example, the same multiple-dose bottle of albuterol was used for many mechanically ventilated patients). More case patients (39 [92.9%]) than controls (95 [70.4%]; P = 0.006) received nebulized albuterol, and case patients (67.5 treatments) received more treatments than controls (18 treatments; P < 0.001). In-use albuterol solutions had pH values that were unstable, and benzalkonium chloride concentrations declined over time to levels capable of supporting bacterial growth. Medication nebulizers and in-use bottles of albuterol harbored B. cepacia. Molecular fingerprints of patient isolates and environmental B. cepacia isolates were identical using repetitive-element PCR. No further isolates of B. cepacia were identified after institution of appropriate infection control procedures. CONCLUSIONS: Multiple-dose medications and reliance on benzalkonium chloride as a medication preservative provide a mechanism for nosocomial spread of microorganisms, particularly if infection control procedures are not carefully followed. Repetitive-element PCR is a useful fingerprinting technique for molecular epidemiologic studies of B. cepacia.

Aged↗

PubMed1994

Fluconazole-induced symptomatic phenytoin toxicity.

OBJECTIVE: To report two cases of fluconazole-induced symptomatic phenytoin toxicity and review literature related to this interaction. DATA SOURCES: Case reports and review articles identified by a computerized (MEDLINE) and manual (Index Medicus) search. DATA SYNTHESIS: Fluconazole is a broad-spectrum triazole antifungal agent primarily eliminated by renal mechanisms, although hepatic cytochrome P-450 inhibition and hepatotoxicity have been observed. We report two cases of fluconazole-induced symptomatic phenytoin toxicity. Both patients received high doses of the drug; one patient developed phenytoin toxicity only after long-term coadministration. Previously reported cases have occurred primarily with high-dose fluconazole and short-term coadministration. CONCLUSIONS: Fluconazole can increase phenytoin serum concentrations leading to toxicity. Constant and continuous monitoring of serum phenytoin concentrations with fluconazole doses as low as 200 mg/d is warranted.

AIDS-Related Opportunistic Infections↗

PubMed1993

Progression from asymptomatic to symptomatic urinary tract infection in patients with SCI: a preliminary study.

The purpose of this prospective pilot study was to (1) evaluate the role of pyuria in predicting the progression from asymptomatic to symptomatic urinary tract infection (UTI) in spinal cord-injured patients who undergo sterile intermittent bladder catheterization and (2) evaluate the impact of treating asymptomatic UTI on this progression. Twenty hospitalized patients were randomized to either the treatment group (10 subjects) or the control group (10 subjects). Weekly urine samples were obtained for quantitation of bacterial growth and pyuria. Neither the level nor the trend of pyuria helped predict the imminent progression to symptomatic UTI. Thirty percent of patients in the treatment group developed symptomatic UTI vs 70 percent of patients in the control group; it took a significantly longer time for patients in the treatment vs control group to develop symptomatic UTI (median number of days: 72 vs 7, respectively; p < 0.003). Further analysis of the long-term impact of antibiotic treatment of asymptomatic UTI is warranted.

Adult↗

PubMed1992

Articular histoplasmosis.

Rheumatic manifestations of histoplasmosis are uncommon. Polyarthritis or arthralgias may occur as a part of a sensitization process in primary acute histoplasmosis. Infectious arthritis may accompany disseminated histoplasmosis or occur as solitary monoarthritis. Treatment of the latter traditionally consists of surgical excision followed by amphotericin B. Reports of clinical experience with the newer triazole compounds in treating articular histoplasmosis are lacking. We describe a patient with solitary monoarticular histoplasmosis of the knee who was successfully treated with oral fluconazole and required no surgical intervention. Specific issues that pertain to clinical presentation and management of articular histoplasmosis are discussed.

Administration, Oral↗

PubMed1991

Vancomycin-induced thrombocytopenia.

Vancomycin-induced thrombocytopenia has only been reported once previously in the medical literature. We describe a patient in whom sudden severe reversible thrombocytopenia developed on two separate occasions after exposure to vancomycin hydrochloride. A 54-year-old man was admitted to the hospital for bilateral swelling and erythema of his extremities. At the time of admission he received 2 days of vancomycin therapy without incident. On day 14 he was reexposed to vancomycin and thrombocytopenia developed, with a nadir value of 17 x 10(9)/L. On day 30, a single dose of vancomycin was administered, and thrombocytopenia once again developed, with a nadir value of 11 x 10(9)/L. Hematologic cytopenias are infrequent adverse effects of vancomycin therapy. It is postulated that these effects may be due to an immunologically mediated mechanism. With the increasing use of vancomycin due to the emergence of methicillin-resistant Staphylococcus aureus, this case should alert clinicians to this rare but potentially lethal manifestation of vancomycin.

Humans↗

PubMed1990

Potential use of aldose reductase inhibitors to prevent diabetic complications.

Reviewed are (1) the biochemical basis and pathophysiology of diabetic complications and (2) the structure-activity relationships, pharmacology, pharmacokinetics, clinical trials, and adverse effects of aldose reductase inhibitors (ARIs). ARIs are a new class of drugs potentially useful in preventing diabetic complications, the most widely studied of which have been cataracts and neuropathy. ARIs inhibit aldose reductase, the first, rate-limiting enzyme in the polyol metabolic pathway. In nonphysiological hyperglycemia the activity of hexokinase becomes saturated while that of aldose reductase is enhanced, resulting in intracellular accumulation of sorbitol. Because sorbitol does not readily penetrate the cell membrane it can persist within cells, which may lead to diabetic complications. ARIs are a class of structurally dissimilar compounds that include carboxylic acid derivatives, flavonoids, and spirohydantoins. The major pharmacologic action of an ARI involves competitive binding to aldose reductase and consequent blocking of sorbitol production. ARIs delay cataract formation in animals, but the role of aldose reductase in cataract formation in human diabetics has not been established. The adverse effects of ARIs include hypersensitivity reactions. Although the polyol pathway may not be solely responsible for diabetic complications, studies suggest that therapy with ARIs could be beneficial. Further research is needed to determine the long-term impact and adverse effects of ARIs in the treatment of diabetic complications.

Aldehyde Reductase↗

PubMed1990

Ampicillin-sulbactam therapy for multiple pyogenic hepatic abscesses.

A patient with multiple, pyogenic hepatic abscesses is described, and the pathophysiology, etiologies, clinical and laboratory manifestations, and management of the disease are reviewed. A 55-year-old man with a history of ethanol abuse and pancreatitis developed fever, chills, general malaise, and right upper quadrant abdominal pain two weeks before hospitalization. Baseline laboratory and hematology results included serum albumin concentration, 3.2 g/dL; serum alkaline phosphatase concentration, 239 mIU/mL; total serum bilirubin concentration, 1.3 mg/dL; white blood cell count, 18,400/cu mm; red blood cell count, 4.7 million/cu mm; hemoglobin, 12.5 g/dL; and hematocrit, 38.8%. Abdominal ultrasound showed echo-free cavities throughout the hepatic parenchyma; abdominal computed-tomography (CT) scan showed hepatomegaly and multiple radiolucent spaces. CT-guided needle aspiration of a hepatic mass yielded purulent material that grew Fusobacterium necrophorum under anaerobic conditions. On day 7, the patient was started on i.v. ampicillin sodium-sulbactam sodium. A CT scan two weeks later showed a reduction in the number and sizes of abscesses. The patient continued i.v. therapy for one month, then was discharged on a regimen of p.o. amoxicillin trihydrate-clavulanate potassium. Hepatic abscesses are either amebic or pyogenic; the latter usually has a higher mortality. The etiologies of pyogenic hepatic abscesses include ascending cholangitis, portal vein bacteremia, systemic bacteremia, extension from a contiguous focus of infection, and trauma. Diagnosis is difficult and relies highly on clinical suspicion. Clinical symptoms include hepatomegaly, fever, chills, and malaise. Abnormal laboratory values include leukocytosis, anemia, and hypoalbuminemia. The abscesses are frequently polymicrobial; Escherichia coli is the most commonly isolated species. CT is the best radiological technique for diagnosis.(ABSTRACT TRUNCATED AT 250 WORDS)

Ampicillin↗