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R Khatib

Publications and source records attributed to R Khatib.

At least 19 recordsLinked to original sources
PubMed2006

Interinstitutional and intrainstitutional transmission of a strain of Acinetobacter baumannii detected by molecular analysis: comparison of pulsed-field gel electrophoresis and repetitive sequence-based polymerase chain reaction.

Pulsed-field gel electrophoresis and repetitive sequence-based polymerase chain reaction provided comparable strain discrimination with minor discordance in typing Acinetobacter baumannii clinical isolates from patients at our hospital and affiliated institutions. Typing revealed a cluster strain with intrainstitutional and interinstitutional spread during the study period. A long-term acute care facility may have been the reservoir.

Acinetobacter Infections↗
PubMed2006

Impact of initial antibiotic choice and delayed appropriate treatment on the outcome of Staphylococcus aureus bacteremia.

The study presented here investigated the impact of initial antibiotic choice (beta-lactams vs vancomycin) on the outcome of 342 patients with Staphylococcus aureus bacteremia (50.9% with methicillin-resistant isolates) encountered between 1 January 2002 and 30 June 2003. Initial antibiotics were inappropriate (beta-lactams) in 60 (34.5%) methicillin-resistant cases and suboptimal (vancomycin) in 62 (36.9%) methicillin-susceptible cases. Time to effective antibiotic therapy was longer in methicillin-resistant cases (25.5+/-28.6 vs 9.6+/-16.6 h; p<0.0005). All-cause in-hospital mortality was higher with inappropriate therapy (35.0 vs 20.9%; p=0.02). Initial vancomycin treatment was associated with a higher incidence of delayed clearance (>or=3 days) of methicillin-susceptible bacteremia (56.3 vs 37.0%; p=0.03). The results indicate inappropriate initial therapy is associated with higher in-hospital mortality and initial vancomycin may delay clearance.

Adult↗
PubMed2004

Repeating blood cultures during hospital stay: practice pattern at a teaching hospital and a proposal for guidelines.

Guidelines for blood culture (BC) address the appropriate frequency, number and volume, but no guidelines exist for repeating BCs. The pattern of repeated BCs was studied in all patients hospitalised in December 2001 to determine the extent of and reasons for repeating cultures. BC was repeated in 127 (31.6%) of 405 adults with an initial BC during the study period. All patients with available records (n = 96; 75.6%) were included. The average patient age was 62.2 +/- 15.9 years. In total, 295 BC sets (one to four BCs/set) were obtained, comprising 96 initial and 199 repeats (one to nine repeats/patient). Sixty-nine (34.7%) repeats were taken within 24 h, and 89 (44.7%) within 2-4 days. The most common reason (32.2%) was persistent fever. The result of repeated cultures was: no growth (83.4%), same pathogen (9.1%), new pathogen (2.5%) or contamination (5.0%). Thus, BC repeats accounted for one-third of all BCs handled in the laboratory, with little additional yield. Guidelines for repeating BCs may decrease unnecessary testing.

Adolescent↗
PubMed2002

Limited genetic diversity of Candida albicans in fecal flora of healthy volunteers and inpatients: a proposed basis for strain homogeneity in clinical isolates.

Molecular analysis of Candida albicans isolates from individual patients often yields a single strain at multiple sites. Whether this strain-limitation is due to virulence factors favoring the invasive strain or to lack of genetic diversity in the gastrointestinal reservoir is uncertain. We elected to study C. albicans genotypes in the fecal flora among healthy volunteers and inpatients. Self-obtained stool swabs or stool samples were cultured on inhibitory mold agar. From each subject with C. albicans, nine colonies were randomly selected, individually propagated, and typed utilizing random amplified polymorphic DNA. Colonies were considered identical (all bands matched), related variants (one to three unique bands), or distinct strains (more than three unique bands). Analysis showed a single clone in 33/43 (76.7%) volunteers and 6/18 (33.3%) inpatients (P = 0.018), two to four related variants in eight (18.6%) volunteers and 10 (55.6%) inpatients, and two distinct strains in two volunteers (4.6%) and two inpatients (11.1%). Strain variation was more common in females (33.5 versus 5.6%; P = 0.04) and tended to increase with age (r = 0.245, P = 0.06). These findings illustrate that most healthy subjects harbor a single strain of C. albicans in the fecal flora. This strain may undergo genetic evolution leading to minor clonal variations. The mechanisms for strain selection, maintenance and possible evolution remain to be delineated.

Candida albicans↗
PubMed2001

Molecular analysis of coagulase-negative Staphylococcus isolates from blood cultures: prevalence of genotypic variation and polyclonal bacteremia.

Fifty-seven coagulase-negative Staphylococcus isolates from 22 inpatients who had > or =2 blood cultures that were positive for Staphylococcus within 24 hours were analyzed to determine the frequency of polyclonal bacteremia. Patients were considered to have bacteremia (14 patients) or contamination of sample (8 patients) on the basis of clinical criteria. Nine colonies were randomly selected from each blood culture and genotyped by means of SmaI digestion/pulsed-field gel electrophoresis. Relatedness was determined by calculation of the Dice coefficient of banding-pattern similarity (S(AB)). Analysis of bacteremic isolates demonstrated the presence of a single species in 35 of 41 blood cultures, 1 related variant in 5 blood cultures (87%-92% S(AB)), and an unrelated strain in 1 blood culture (79% S(AB)). Analysis of contaminated samples demonstrated the presence of a single strain in 10 of 16 blood cultures and 1-3 variants (28%-97% S(AB)) in the remainder. Genotype diversity was significantly more common in the contaminated samples (P=.036). Almost all coagulase-negative Staphylococcus bacteremias were monoclonal.

Adult↗
PubMed2001

Recurrent vancomycin-resistant Enterococcus bacteremia: prevalence, predisposing factors, and strain relatedness.

We studied the prevalence of recurrent vancomycin-resistant Enterococcus (VRE) bacteremia, predisposing factors, and strain relatedness during a 3 year period at our institution. Of 36 inpatients who had episodes of bacteremia, 3 (8.3%) had recurrent episodes. Predisposing factors were mucositis and neutropenia (1 patient) and chronic renal failure requiring hemodialysis (2). Recurrent episodes separated by < or = 3 months were caused by identical or related strains, and those at greater intervals by distinct strains. Recurrent VRE bacteremia is uncommon.

Adult↗
PubMed2001

Faecal fungal flora in healthy volunteers and inpatients.

The faecal fungal flora was analysed in healthy volunteers and inpatients. Self-obtained stool swabs from volunteers (n = 228) and inpatient stool-samples (n = 34) were cultured on Inhibitory-Mould-Agar plates. All yeast isolates were identified. Fungi were detected in 51.8% of volunteers; the majority (88.1%) had single species. The prevalence increased steadily with age. Candida albicans was detected in 62.7%, non-albicans Candida species in 22.0%, yeasts--other than Candida in 20.3% and moulds in 8.5% of volunteers with fungi. No gender-related differences were noted in the prevalence or types of yeast. Candida glabrata and C. krusei were detected in adults only. Intra-household species-similarity (excluding C. albicans) was noted in seven of 31 (22.6%) households with fungi in two or more members. Inpatients had higher prevalence of yeast (88.2%) with a single species in the majority (73.3%). Yeasts other than Candida were less common in inpatients (3.3%; P = 0.013) whereas C. glabrata was significantly more prevalent (33.3 versus 2.5%; P < 0.001). This study delineates the faecal fungal flora in volunteers and inpatients. Most subjects harbour a single species that may be shared with other households. The prevalence is somewhat higher in adults and the types of yeast may vary with age. Finally, C. glabrata appears to be acquired nosocomially.

Adolescent↗
PubMed2001

Meningococcemia following tonsillectomy.

A 22-y-old male developed fever, arthralgias and skin rash 2 d after tonsillectomy. Blood culture grew Neisseria meningitidis. He responded well to antibiotics. Only 1 other case of meningococcal sepsis following adenotonsillectomy has previously been reported. These cases suggest a temporal association of meningococcemia with tonsillectomy.

Adult↗
PubMed2001

Candidemia before and during the fluconazole era: prevalence, type of species and approach to treatment in a tertiary care community hospital.

The characteristics of candidemia before and after the introduction of fluconazole were compared at our institution. In the pre-fluconazole era (1986-89), the incidence of candidemia rose from 0.02% to 13% over the course of 4 y. Candida albicans accounted for 44/66 isolates (67%) and C. glabrata and C. parapsilosis were the predominant non-albicans species (9% each). In one-third of cases antifungal therapy was not given and the overall mortality rate was 55%. During the fluconazole era (1994-97), the incidence of candidemia remained constant between 1994 and 1996 at 0.09-0.11% and dropped to 0.06% in 1997. Bloodstream infection associated with neutropenia increased significantly but only accounted for 13% of cases; antifungal prophylaxis was not employed. The isolation of C. albicans decreased (n = 49; 50%) whereas isolation of both C. parapsilosis (n = 23; 24%) and C. tropicalis (n = 16; 16%) increased. The vast majority of patients received antifungal therapy and the overall mortality rate was 39%. These findings show that the incidence of candidemia rose steadily prior to the fluconazole era and then stabilized in spite of a shift towards non-albicans species. When candidemia was encountered in the fluconazole era, it was rare not to give antifungal treatment.

Adolescent↗
PubMed2000

Limits of detection of Mycobacterium tuberculosis in spiked cerebrospinal fluid using the polymerase chain reaction in tuberculous meningitis.

The limit of detection of Mycobacterium tuberculosis in spiked cerebrospinal fluid (CSF) using polymerase chain reaction (PCR) was compared to that of a radiometric liquid culture. Serial dilutions of clinical isolates of Mycobacterium tuberculosis were prepared in CSF (n=3) or broth (n=11) with estimated concentrations of 0-550 cfu/ml. Each dilution was examined concurrently by PCR and radiometric culture. PCR and radiometric culture detected Mycobacterium tuberculosis DNA in all dilutions with an estimated 2 cfu/ml in the CSF. At lower concentrations (estimated <2 cfu/ml), PCR and radiometric culture were positive in three of five (60%) and five of five (100%) CSF samples, respectively. In comparison to PCR in broth dilutions, no evidence of inhibition or interference was noted. These results imply that PCR can provide a rapid and reliable diagnosis of tuberculous meningitis, although there is a potential for false-negative results to occur in samples containing very few organisms ( < 2 cfu/ml).

Cerebrospinal Fluid↗
PubMed2000

Pyopneumothorax: a complication of Streptococcus pyogenes pharyngitis.

A 20-y-old African-American female with Streptococcus pyogenes pharyngitis presented with tension pyopneumothorax. Her illness began with fever and sore throat that persisted for several days. She then developed a left neck swelling, followed by difficult swallowing and cough. Subsequently, she developed shortness of breath that became severe. On physical examination fever (39.2 degrees C), exudative pharyngitis, tenderness and swelling in the left anterior cervical area were noted. Chest X-ray revealed left side pneumothorax, air-fluid level and near-complete collapse of the left lung with displacement of the heart and trachea to the right. Computed tomography scan of the neck revealed swelling and enhancement of the sternocleidomastoid muscle with loculated fluid collection, inflammation in the left anterior medial neck displacing the trachea extending into the mediastinum and the left apex. Thoracentesis revealed purulent fluid; Gram stain showed Gram-positive cocci in chains; culture yielded pure growth of Streptococcus pyogenes. She was treated with high dose penicillin, several chest tubes and intra-pleural injections of streptokinase with gradual resolution. This complication has not been described previously in Streptococcus pyogenes pharyngitis.

Adult↗
PubMed2000

Herpes simplex virus esophagitis in the immunocompetent host: an overview.

OBJECTIVE: The aim of this study was to delineate the characteristics of herpes simplex virus esophagitis (HSVE) in the immunocompetent host. METHODS: The study entailed a case report and a review of relevant literature through a MEDLINE search back to 1966. All cases with documented HSVE in patients without immunosuppression were selected and their characteristics defined. RESULTS: A total of 38 cases were identified. The age range was 1-76 yr and the male/female ratio 3.2/1. Antecedent exposure to HSV disease was described in eight cases (21.1%). A prodrome of systemic manifestations preceded the onset of esophageal symptoms in nine subjects (23.6%). Manifestations included acute odynophagia (76.3%), heartburn (50%), and fever (44.7%). Concurrent oropharyngeal lesions were uncommon (n = 8, 21.1%). Endoscopically, extensive involvement was common, showing friable mucosa (84.2%), numerous ulcers (86.8%), and whitish-exudates (39.5%). The distal esophagus was most commonly affected (63.8%). Microscopic examination showed characteristic viral cytopathology in 26 (68.4%) cases. Virus was recovered from esophageal-brushes or biopsies in 23 of 24 (95.8%) patients and immunocytochemistry was positive in seven of eight (87.5%) cases. Immune status was consistent with primary HSV infection in eight (21.1%) cases. The disease was self-limiting, although esophageal perforation and upper GI bleeding were reported in one case each. CONCLUSIONS: HSVE in the immunocompetent host is a rare but distinct entity, and is significantly more common in male subjects. It represents either primary infection or reactivation, and is characterized by acute onset, systemic manifestations, and extensive erosive-ulcerative involvement of the mid-distal esophagus. Histopathological examination alone may miss the diagnosis; adding tissue-viral culture optimizes the diagnostic sensitivity. It is usually self-limiting; whether antiviral therapy is beneficial remains unknown.

Acyclovir↗
PubMed2000

Trends in antifungal susceptibility among Candida sp. Urinary isolates from 1994 and 1998.

Antifungal susceptibilities were determined from 80 urinary isolates of Candida species collected in 1994 and 1998. Our findings demonstrate increasing geometric means of fluconazole MICs and fluconazole resistance in Candida albicans and Candida tropicalis (those for Candida glabrata were unchanged) within the 4-year span. Amphotericin B and voriconazole MICs remained constant.

Antifungal Agents↗
PubMed1999

Clinicians' reaction to positive urine culture for Candida organisms.

Clinicians' reaction to isolating Candida organisms in urine culture (> or = 10(4) CFU ml-1) was assessed in a retrospective review of 133 consecutive in-patients (> or = 15 years-of-age) over a 5 month period. The average age was 68.8 years and male/female ratio was 0.36 (35/98). Most (78.2%) patients had an indwelling catheter, and many (35.3%) were in the intensive care unit (ICU). In response to culture-result, clinicians initiated antifungal therapy in 80 instances (60.2%). Treatment was often based on a single culture without documenting the infection (n = 53/80, 66.3%) in the absence of risk for invasive disease. Removing the indwelling-catheter was never attempted and antibiotics were rarely discontinued or modified (1.3%). Fluconazole was most frequently utilized (n = 42, 52.5%), followed by amphotericin-B bladder-irrigation (n = 26, 32.5%), and combined fluconazole/amphotericin-B bladder-irrigation (n = 12, 15%). Therapy was more frequently initiated in ICU-cases (76.6 versus 55.6%; P = 0.023) and less often in non-catheterized individuals (40.7 versus 69%; P = 0.012) and patients with 10(4) CFU ml-1 (25.9 versus 72.7%; P < 0.0001). These findings show that clinicians nowadays do not follow current guidelines for the management of candiduria. Efforts to increase clinicians' awareness of these guidelines, which are intended to confirm the diagnosis and stratify treatment according to patient risk factors, appear to be necessary.

Adolescent↗
PubMed1999

Sequential peripartum herpes simplex virus type 2 disease in parents and their newborn mimicking intrafamily spread of common viruses.

Herpes simplex type 2 (HSV2) disease developed sequentially among two parents and their newborn. The father first became ill with upper-respiratory symptoms and fever. Then, 5 days later, shortly after delivery, the mother had fever, pharyngitis, and diarrhea. Subsequently, the infant developed undifferentiated febrile illness at the age of 3 days. HSV etiology was recognized by incidental isolation of HSV2 from the newborn naospharynx. The father never developed genital lesions and the mother's symptoms remained nonspecific for several days prior to the onset of genital manifestations. The sequential emergence and manifestations of these infections could have been misconstrued for an intrafamily spread of respiratory or enteric viruses. This cluster illustrates that HSV2 may cause sequential symptomatic disease in susceptible individuals mimicking other viruses.

Adult↗