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R Khatib

Publications and source records attributed to R Khatib.

At least 37 records · Page 2Linked to original sources
PubMed1998

Strain relatedness in persistent and recurrent candiduria.

PURPOSE: We assessed the value of determining strain relatedness in differentiating persistent from recurrent candiduria. MATERIALS AND METHODS: Prospective monitoring of patients with candiduria (10(4) or greater colony forming units per ml.) during a 5-month period. All patients with persistent or recurrent infection after documented clearance were selected. Pair isolates were typed using restriction endonuclease analysis of genomic deoxyribonucleic acid with SfiI. Isolates were considered related if all deoxyribonucleic acid bands matched. RESULTS: We encountered 22 and 5 patients with persistent and recurrent infection, respectively. The isolates were recovered 1 to 140 days apart (21.56 +/- 28.97). Most patients were women (85.2%) with a mean age of 66.41 +/- 18.11 years. Risk factors included antibiotics (100%), indwelling catheter (88.9%) and diabetes mellitus (40.7%). Of 15 individuals who received antifungal therapy candiduria persisted in 10 and resolved but recurred within 4 to 26 days (13.00 +/- 9.08) after treatment in 5. Candida albicans accounted for 34 of 58 isolates (58.6%), and it was mixed with other species in 4 cultures. Paired strains were genetically identical in 26 of 27 patients. Strain persistence was documented in 21 of 22 cases with persistent infection and in all 5 patients with recurrent disease. CONCLUSIONS: These findings show that strain persistence is exceedingly frequent in candiduria. These results imply that determining strain relatedness of Candida urinary isolates may not be reliable in differentiating persistent from recurrent infection.

Aged↗
PubMed1998

Tricuspid valve endocarditis due to a moderately susceptible Streptococcus constellatus: persistent bacteremia and fatal outcome despite penicillin plus gentamicin therapy.

An intravenous drug-user developed tricuspid valve endocarditis caused by a moderately susceptible strain of Streptococcus constellatus. Bacteremia and fever persisted despite penicillin and gentamicin therapy. Eventually, he developed massive hemoptysis and expired. We believe that the propensity of this group of organisms for suppurative complications and the suboptimal antibiotic susceptibility may have contributed to the failure of medical therapy and the fatal outcome. Similar cases may benefit from a higher dose of penicillin or early surgical intervention.

Adult↗
PubMed1998

Cytomegalovirus colitis in the immunocompetent host: an overview.

This paper describes 2 immunocompetent patients with cytomegalovirus colitis and reviews all previously reported cases (n = 13). Affected patients were generally older (69.13+/-15.62 y-old) with probable reactivation (n = 8) or younger (43.86+/-19.73 y-old) with probable primary infection (n = 7). The onset of illness was found to be hospital-associated in 4 (50.0%) reactivation cases and 1 (14.3%) primary case. Presenting manifestations included diarrhoea (86.7%), fever (80.0%), gastrointestinal bleeding (66.7%) and abdominal pain (60.0%). Endoscopy showed erosive colitis with multiple (n = 11; 73.3%) or single ulcers (n = 2, 13.3%); biopsy was diagnostic in 12/13 (92.3%) patients. Complications included massive haemorrhage (13.3%), toxic megacolon (13.3%), perforation (13.3%) and protracted inflammatory bowel disease (20.0%; exclusively in primary-infection). The mortality rate was 26.7%. Antiviral-agents were given in 8 (53.3%) cases; assessment of treatment-efficacy was not possible. In conclusion, cytomegalovirus colitis in the immunocompetent-host is a rare but potentially severe erosive disease with significant morbidity. It may occur during primary infection or reactivation; the diagnosis requires careful histopathological examination and the benefit of antiviral-therapy is unknown.

Aged↗
PubMed1998

Clustering of Candida infections in the neonatal intensive care unit: concurrent emergence of multiple strains simulating intermittent outbreaks.

BACKGROUND: Clusters of Candida albicans and Candida parapsilosis infections were noted intermittently in our neonatal intensive care unit (NICU). We attempted to determine whether these clusters represented single strain outbreaks or coincidental emergence of unrelated strains. METHODS: A retrospective examination of the frequency of candidemia during a 9-year period, two point prevalence studies of colonization and assessment of strain relatedness of individual infant isolates during and in between clusters during a 2-year period with karyotyping and restriction endonuclease analysis of genomic DNA (REAG). RESULTS: C. albicans and C. parapsilosis infections emerged in a scattered pattern (1 to 2 cases every few months) with intermittent clustering of 3 cases/month. The colonization rate was 50% 5 weeks after an apparent cluster, equally distributed between C. albicans and C. parapsilosis, and 17.6% (exclusively with C. parapsilosis) 4 months after absence of invasive disease. Utilizing REAG or karyotyping singly we noted 12 and 16 DNA banding patterns, respectively, among 23 infant isolates. Few patterns were observed repeatedly over 2- to 20-month periods, implying recurrent emergence of the same strains. Combining karyotyping with REAG revealed a different epidemiologic pattern. It identified 20 distinct composites with identical composites in 3 infant pairs. All infants with identical composites were in the NICU concurrently. The frequency of strain relatedness was comparable among clustered cases (16.7%), scattered cases (7.7%) and simultaneously colonized infants (16.7%). CONCLUSIONS: These findings illustrate that Candida infections clustered periodically in our NICU but that these clusters were often caused by unrelated strains with infrequent cross-infection during and between clusters. With suboptimal typing this pattern of emergence can be mistaken for same strain outbreaks.

Candida↗
PubMed1998

Typing of Candida albicans and Candida parapsilosis: species-related limitations of electrophoretic karyotyping and restriction endonuclease analysis of genomic DNA.

Species-related discrimination limits of electrophoretic karyotyping (EK) and restriction endonuclease analysis of genomic DNA (REAG), using pulse-field gel electrophoresis, in typing Candida albicans (CA) and Candida parapsilosis (CP) were compared. Eleven CA and 12 CP isolates from individual neonates and three CA and three CP control isolates were used. For CA, EK and REAG with sfiI displayed seven and six banding-patterns, respectively. One karyotype and two SfiI banding-patterns were observed among the control-isolates. Combining EK/REAG (SfiI) demonstrated nine composites and three distinct control-composites. For CP, EK displayed nine karyotypes, REAG (SfiI) demonstrated four banding-patterns, and REAG (BssHII) yielded six banding-patterns. EK and REAG/SfiI failed to distinguish any CP-controls whereas REAG/BssHII distinguished 2/3 CP-controls. Combining EK/REAG (SfiI) showed 10 composites indistinguishable from CP-controls whereas EK/REAG (BssHII) demonstrated 11 composites and three distinct control-composites. These results illustrate that singly, EK and REAG have significant limitation in typing Candida species though EK is more precise. Combining both methods yields better results but the appropriate restriction endonuclease may vary by strains or species. These findings underscore the importance of combining multiple typing methods, testing several control isolates, and correlating the results with careful epidemiological assessment.

Adult↗
PubMed1998

Prolonged Captopril Therapy in Murine Viral Myocarditis.

BACKGROUND: Acute myocarditis can progress to chronic heart muscle disease and cardiomyopathy. In the coxsackievirus B(3) (CB(3)) mouse model of myocarditis, early administration of captopril, an angiotensin-converting enzyme (ACE) inhibitor, ameliorated histopathological changes in inflammation, necrosis, and calcification and reduced heart weight. Late administration of captopril reduced heart weight but did not affect the histological findings. In this study, we investigated the effects of prolonged captopril treatment in the chronic phase of this model. METHODS AND RESULTS: Three-week-old male CD(1) mice were infected with CB(3) and then randomized to receive placebo or captopril starting on day 7 of infection. Captopril, 2 g/L, was given as the drinking water daily for up to 6 months. Autopsies were performed at 6 and 10 months. Heart-to-body weight ratios were obtained, and deaths were tallied. Myocardial fibrosis was graded according to a score system. In addition, picrosirius red stain (PSR) also was used for assessment of collagen deposition. Mean heart weights were similar in both groups. Mean body weight was significantly lower in captopril-treated mice (40.7 g) than in the untreated group (43.6 g) at 6 months (P =.0155), and mortality was higher (8.7 vs 0.87%; P =.009). At 6 months, the mean myocardial fibrosis score in treated mice (0.12) was significantly less than in untreated animals (0.35; P =.035). With PSR, the mean myocardial fibrosis score in the captopril group (1.20) was also significantly less than in the untreated group (1.58; P =.045). At 10 months, fibrosis scores were similar in both groups. CONCLUSIONS: Chronic captopril treatment in CB(3) myocarditis reduces myocardial fibrosis.

Journal Article↗
PubMed1997

Respiratory isolation in a teaching hospital with low-to-moderate rate of tuberculosis: compliance with Centers for Disease Control and Prevention guidelines for identifying patients who may have active tuberculosis.

BACKGROUND: Because of the limitation of isolation spaces suitable for tuberculosis, proper use of these spaces is prudent. We examined the current approach to respiratory isolation to determine the compliance with Centers for Disease Control and Prevention (CDC) guidelines for identifying active tuberculosis. METHODS: A retrospective review was performed of all patients placed in respiratory isolation and those with pulmonary tuberculosis. RESULTS: Seventy-seven instances of isolation and three admissions without isolation were encountered. Isolated patients met CDC guidelines for infectiousness in 59 of 77 instances (76.6%). The remaining patients were isolated with findings not characteristic of active tuberculosis (10 instances), normal chest radiograph (6 occasions), or without chest radiograph (2 instances). The time of implementing isolation was the first hospital day in 58 instances (75.3%) and 2 to 14 days in 19 instances (24.7%). Isolated human immunodeficiency virus-infected patients were more likely to meet CDC guidelines for infectiousness (21/22 [95.5%] vs 38/55 [69.1%] instances) and to be isolated on a timely basis (18/22 [81.8%] vs 40/55 [72.7%]). Tuberculosis was documented in 15 instances and isolation was delayed or never implemented in 5 and 3 instances, respectively. CONCLUSIONS: Compliance with CDC guidelines for respiratory isolation in patients not infected with human immunodeficiency virus is suboptimal. Many isolated patients do not meet these guidelines, and isolation is delayed or not implemented in patients who may have tuberculosis.

Adult↗
PubMed1995

Massive esophageal bleeding in achalasia complicated by cytomegalovirus esophagitis.

A 69-year-old man with achalasia who had received cytoxan and prednisone over a 6-week period for presumed Wegener's granulomatosis presented with massive esophageal bleeding. He did not respond to aggressive medical management, and an emergent esophagectomy was performed. Histologic examination revealed extensive cytomegalovirus esophagitis. He had a long but progressive hospital course and was discharged 1 month after admission. This case illustrates that cytomegalovirus esophagitis may cause massive hemorrhage that necessitates surgical intervention.

Aged↗
PubMed1995

Coagulase-negative staphylococci in multiple blood cultures: strain relatedness and determinants of same-strain bacteremia.

The frequency of strain relatedness was determined among randomly selected patients with coagulase-negative staphylococcal infections as determined in multiple blood cultures by plasmid typing, determination of species, and antibiotyping. Strain relatedness was demonstrated in 21 of 47 episodes of bacteremia (44.7%) among 34 patients, with a similar percentage among patients with two or one positive blood culture in 24 h (14 of 30 [46.7%] versus 7 of 17 [41.2%], respectively). Same-strain bacteremia was more frequent in cases of infection among patients with a corresponding fever (15 of 21 [71.4%]), among patients infected with organisms from an identifiable source (7 of 9 [77.8%]) and with non-Staphylococcus epidermidis species (9 of 11 [81.8%]), and among patients with nosocomially acquired infections (18 of 36 [50%]). Comparing episodes with or without strain relatedness, no difference was noted in the time to growth (2.1 +/- 1.4 versus 1.9 +/- 0.9 days, respectively), in bacterial growth in two culture bottles (5 of 14 [35.7%] versus 8 of 24 [33.3%], respectively), and in the presence of additional negative blood cultures (9 of 21 [42.9%] versus 11 of 26 [42.3%], respectively). The antibiotypes of all related strains and 7 of 44 (15.9%) unrelated pairs were identical. These findings demonstrate that coagulase-negative staphylococci from multiple blood cultures are frequently unrelated, suggesting a high prevalence of contamination. In the absence of precise measures for demonstrating strain relatedness, the combination of a clinical assessment with antibiotype determination appears to be a suitable alternative.

Adolescent↗
PubMed1995

Relevance of culturing Candida species from intravascular catheters.

The significance of isolating Candida species from intravascular catheters was examined retrospectively. Our findings demonstrate that these organisms are encountered among patients with proven invasive candidiasis or as an isolated finding. Febrile patients with yeasts in two or more additional sites may be at risk for invasive cadidiasis and may benefit from treatment.

Adolescent↗
PubMed1995

Diagnosis of Clostridium difficile associated diarrhea: comparison of three rapid methods employing different markers for detection.

Latex agglutination and the enzyme immunoassays Cytoclone (EIA-C) and VIDAS (EIA-V) were compared with a cytotoxicity assay for the diagnosis of Clostridium difficile associated diarrhea. Among patients with discrepant results, the cytotoxicity assay and clinical assessment were used to evaluate the performance of the latex agglutination and EIA tests. Clostridium difficile associated diarrhea was documented in 30/149 samples (20.1%) from 130 patients. All test results matched in 113 instances. Latex agglutination, EIA-C, and EIA-V yielded false positive results in 10, 4, and 7 samples and false negative results in 8, 9, and 14 samples, respectively. Latex agglutination demonstrated 87.8% efficiency compared with 91.3% for EIA-C and 85.7% for EIA-V and 3 min hands-on time compared with 4.5 min for EIA-V and 10 min for EIA-C. On the basis of these findings and given the fact that all rapid tests have their shortcomings, we believe that latex agglutination is the most practical method.

Biomarkers↗
PubMed1995

Severe psittacosis during pregnancy and suppression of antibody response with early therapy.

A cluster of 3 cases of psittacosis occurred among members of one family. The initial case was a pregnant woman who presented with extensive multilobar infiltrates and severe respiratory distress necessitating mechanical ventilation. Her respiratory failure worsened during 36 h of erythromycin therapy. Improvement coincided with the termination of pregnancy and the initiation of doxycycline treatment. The remaining patients developed milder illness. Serologic assessment of the affected subjects suggests that early treatment may suppress antibody response.

Adolescent↗
PubMed1995

Protracted and recurrent methicillin-resistant Staphylococcus aureus bacteremia despite defervescence with vancomycin therapy.

Methicillin-resistant Staphylococcus aureus (MRSA) bacteremia persisted for 46 days in a 63-year-old patient and recurred over 98 days in a 79-year-old patient, despite vancomycin therapy. Although the fever resolved, patient 1 developed a spinal epidural abscess 38 days after beginning therapy and patient 2 sustained multiple relapses. A time-kill study demonstrated a reduced vancomycin killing rate in both isolates when compared to the killing rate of a control MRSA strain. The bacteremia persisted after increasing the vancomycin dose to achieve trough levels of 15-20 micrograms; it cleared after adding gentamicin. These cases illustrate that MRSA bacteremia may persist during vancomycin therapy despite resolution of fever and may lead to delayed complications, and that adding gentamicin may be necessary for ultimate clearance of the bacteremia.

Aged↗