Clinical manifestations and risk factors of Pseudomonas aeruginosa infection in patients with AIDS.

Fifty-eight patients with human immunodeficiency virus infection were analyzed for clinical manifestations and potential risk factors for Pseudomonas aeruginosa infection by use of case-control methodology. Most had AIDS. Of 73 episodes of P. aeruginosa infection, 45 (62%) were bacteremias primarily associated with central venous catheters (16), pneumonia (12), soft tissue (4), or urinary tract infections (4). Twenty-eight episodes (38%) were nonbacteremic, with pneumonia (13), soft tissue infections (6), and sinusitis (4) accounting for the majority of infections. Fifty episodes (68%) were community-acquired. The recurrence rate was 23%. The overall mortality attributable to P. aeruginosa infection was 22%. Central venous and urinary catheter use and steroid therapy were significantly more frequent in cases than controls (P < .05). Thus, P. aeruginosa infection in patients with advanced human immunodeficiency virus disease is often community-acquired and associated with substantial mortality and, in some cases, specific risk factors.

Modification of Emit assay reagents for improved sensitivity and cost effectiveness in the analysis of hemolyzed whole blood.

This report describes an improved method for the direct detection of a broad spectrum of drugs of abuse in hemolyzed whole blood by means of Syva Emit enzyme immunoassay. Improvements include a 1.5 to 10 fold increase in Emit assay sensitivity along with a 2 to 4 times increase in the normal number of assays per kit. This was accomplished by enzyme substrate and cofactor supplementation with a commercially available product (Raichem), assay reagent dilution, and extension of the absorbance measure time. The Emit drug abuse in urine (d.a.u.) assays used in this study included amphetamine, barbiturate, methadone, methaqualone, opiate, benzodiazepine metabolite, phencyclidine, and propoxyphene. The Emit serum assays used were the benzodiazepine and the tricyclic antidepressant assays. The within-run coefficients of variation ranged from 0.25 to 0.66%, and the between-run coefficients of variation ranged from 0.45 to 1.00%. The proposed method allows for the analysis of hemolyzed whole blood using both Emit d.a.u. and serum assays. It is sensitive and can detect therapeutic or subtherapeutic concentrations of drugs in all assays tested. The method is simple, rapid, and allows for the direct analysis of a methanolic extract of whole blood without lengthy sample concentration steps. The method allows for the detection of highly potent drugs and for long-term monitoring of drug metabolites and conjugates. This could be beneficial for therapeutic drug monitoring, assessing patient compliance, and detection of previous drug use.

Sinusitis in HIV-infected patients: a clinical and radiographic review.

PURPOSE: To describe the clinical, radiographic, and laboratory features of sinus disease in human immunodeficiency virus (HIV)-infected individuals. PATIENTS: Seventy-two patients with a history of sinusitis identified from 1,461 consecutive admissions (667 patients) to the HIV ward at The Johns Hopkins Hospital. METHODS: Retrospective chart review. SETTING: The Johns Hopkins Hospital. RESULTS: Sinusitis was identified in 72 HIV-infected patients, predominantly individuals with a CD4 cell count of less than 200/mm3. A history of respiratory infections such as bacterial pneumonia, bronchitis, and otitis media was common. Although nasal congestion and postnasal drainage were found in the majority of patients, symptoms of sinusitis were often nonspecific and the diagnosis was incidental in 28 patients (33%). Magnetic resonance imaging or computed tomography was significantly more sensitive than plain radiography (p less than 0.001) in defining the extent of the disease, particularly with posterior sinus involvement, which occurred in the majority of the patients. The number of radiologically abnormal sinuses correlated inversely with the CD4 count. Although the majority of patients responded at least partially to antibiotic therapy, only 15% had complete resolution of clinical symptoms. Fifty-eight percent of patients had clinical and/or radiographic evidence of recurrent/persistent sinus infection, and chronicity correlated with a CD4 count less than 200/mm3 (p less than 0.001). CONCLUSIONS: Sinusitis in HIV-infected patients is common, severe, and difficult to treat. Patients with CD4 counts less than 200/mm3 are prone to disease involving multiple sinuses that responds incompletely to antibiotic therapy, often resulting in chronic sinusitis. Unlike the immunocompetent host, the majority of the HIV-infected patients with advanced immunodeficiency develop posterior sinus disease.

Direct detection of therapeutic concentrations of tricyclic antidepressants in whole hemolyzed blood using the EMITtox serum tricyclic antidepressant assay.

A simple, rapid, and sensitive method for the direct detection of tricyclic antidepressant drugs in whole hemolyzed blood using an enzyme immunoassay technique is described. A methanolic extract prepared from as little as 200 microL of whole blood is analyzed directly using the EMITtox serum tricyclic antidepressant assay, allowing it to be used with whole blood rather than only serum. The minimum detectable concentration of most of the tricyclics is in the range of 25-50 ng/mL, a therapeutic or subtherapeutic, rather than toxic, concentration. The proposed assay shows excellent precision with a mean coefficient of variation (CV) of 0.7%. The cross-reactivity of 12 tricyclic antidepressant drugs is reported. The relationship between drug structure and relative assay response is thoroughly investigated. The relative assay response due to each of nine separate molecular features is calculated. The relationship between the molecular structure and EMIT assay response on a molar basis is shown to be not only quantitative but also additive. This should allow the quantitative prediction of EMIT assay response for drugs or compounds having similar structures.

Use of the EMITtox serum tricyclic antidepressant assay for the analysis of urine samples.

The EMITtox serum tricyclic antidepressant (TCA) assay is intended for use with serum or plasma. Currently, there are no commercially available immunoassay kits available for the detection of TCAs in urine. The proposed method utilizes the EMITtox serum TCA assay for the direct analysis of urine samples. The minimum detectable concentration of nortriptyline in urine is 25 ng/mL. The within-run CV was determined to be 0.6% and the between-run CV was 2.6%. The TCA assay cross-reacts with phenothiazines and antihistamines. The proposed methodology should be applicable to other EMIT serum assays to allow their use with urine.

Direct detection of drugs of abuse in whole hemolyzed blood using the EMIT d.a.u. urine assays.

A simple, rapid, and sensitive method for the direct detection of a broad spectrum of drugs of abuse in hemolyzed whole blood by the enzyme multiplied immunoassay technique (EMIT) is described. A methanolic extract of 1 mL of whole blood is directly analyzed with EMIT urine assays. The proposed method is very sensitive and can detect drug concentrations in low therapeutic to subtherapeutic concentration ranges for all ten assays used. The EMIT urine assays used in this study included those for opiates, amphetamines, methadone, barbiturates, phencyclidine (PCP), methaqualone, propoxyphene, cocaine metabolite, benzodiazepine metabolite, and cannabinoids. This method should be most useful for screening forensic cases by EMIT when no urine is available, such as in impaired driving cases.