Cutaneous non-tuberculous Mycobacterial infections: a clinical and histopathological study of 17 cases from Lebanon.

BACKGROUND: Only a few studies characterized cutaneous non-tuberculous Mycobacterium (NTM) infections in this region of the world. Objective The aim of this study was to describe the epidemiological, clinical and histological findings of cutaneous NTM infections in Lebanon. PATIENTS/METHODS: Retrospective study of 17 patients (19 histological specimens) diagnosed with cutaneous NTM infections and confirmed by culture-based partial sequencing of the 16S rRNA gene at the American University of Beirut Medical Center between 2005 and 2008. RESULTS: Of 17 cases, 14 were caused by Mycobacterium marinum. All patients were immunocompetent except for one. Clinically, the most common presentation was multiple sporotrichoid lesions over an extremity (8/17). Many patients had peculiar presentations including bruise-like patches, herpetiform lesions, annular ulcerated plaques, symmetrical nodules over the buttocks and locally disseminated lesions with surrounding pale halo. Almost all patients cleared their infection on either minocycline or clarithromycin monotherapies. Histologically, a dermal small vessel proliferation with mixed inflammation (granulation tissue-like changes) was identified in 58% of specimens. The most common type of granulomatous inflammation was the suppurative (47%) followed by the tuberculoid (30%), sarcoidal (11%), and palisading (5%) types. Lichenoid granulomatous dermatitis was noted in 42% of cases. Special staining highlighted mycobacteria in only two specimens. CONCLUSIONS: The incidence of cutaneous NTM infections is high in our area. Many patients had peculiar clinical presentations. Our study is the second to report the common presence of granulation tissue-like changes as a good histological indicator of cutaneous NTM infections. Minocycline and clarithromycin remain the drugs of choice in our area.

Staphylococcus aureus nasal carriage rate and associated risk factors in individuals in the community.

The increasing prevalence of Staphylococcus aureus and methicillin-resistant S. aureus (MRSA) strains together with their disease impact on hospital patients and individuals in the community has posed a major challenge to healthcare workers. This study examined the prevalence of S. aureus nasal carriage, antimicrobial susceptibility patterns, and possible risk factors in the community. Of 500 studied subjects (aged from 6 to 65 years) in Lebanon, the overall S. aureus nasal carriage rate was 38.4%, the highest (57.1%) being in children aged 6-10 years. Only eight individuals (1.6%) were carriers of MRSA. Risk factors for S. aureus nasal colonization were male gender, young age, contact with healthcare workers, use of needle injections, and having asthma. A significant decrease in colonization rate was associated with nasal wash with water, use of nasal sprays, and the presence of acne. These findings may assist in better understanding of control measures to decrease nasal colonization with S. aureus in Lebanon and elsewhere.

Molecular characterization of Staphylococcus aureus in Lebanon.

Staphylococcus aureus is an important human pathogen and is a growing public health concern. In this study, 130 S. aureus, 93 methicillin-resistant S. aureus (MRSA) and 37 methicillin-sensitive S. aureus (MSSA), clinical isolates recovered from Lebanon were typed by protein A gene (spa) sequencing and multi-locus sequence typing (MLST). Forty-eight different spa types were identified and clustered into 30 different groups. MLST revealed 10 sequence types (STs) among the isolates. There were eight major MRSA clones defined as isolates with the same ST and the same SCCmec type. The majority of the PVL-positive isolates (53%) were ST80-MRSA-IVc. Systematic surveillance of both hospital and community isolates in Lebanon together with measures designed to limit the spread are required.

First detection of oxacillinase-mediated resistance to carbapenems in Klebsiella pneumoniae from Morocco.

The frequency of carbapenem resistance due to class-D beta-lactamases (i.e. oxacillinases) among the world's Enterobacteriaceae is increasing. Recently, in Morocco, two isolates of carbapenem-resistant Klebsiella pneumoniae were recovered from the same patient, one harbouring plasmid-encoded bla-(OXA-48) and the other the bla-(OXA-1) gene. This represents the first evidence of bla(OXA-48)-mediated carbapenem-resistance in Enterobacteriaceae in Morocco.

Molecular characterisation of extended-spectrum beta-lactamase-producing Escherichia coli and Klebsiella spp. isolates at a tertiary-care centre in Lebanon.

The prevalence of bla CTX-M, bla TEM and bla SHV genes among extended-spectrum beta-lactamase (ESBL)-producing clinical isolates of Escherichia coli (n = 50) and Klebsiella spp. (n = 50) from Lebanon was 96%, 57% and 67%, and 40%, 82% and 84%, respectively. Genotyping revealed that the clonal diversity was unrelated to the presence of bla genes. Sequence analysis of 16 selected isolates identified the bla CTX-M-15, bla TEM-1, bla OXA-1 and six bla SHV genes, as well as the gene encoding the quinolone-modifying enzyme AAC(6')-Ib-cr. The genes encoding CTX-M-15 and AAC(6')-Ib-cr were carried on a 90-kb plasmid of the pC15-1a or pCTX-15 type, which transferred both ESBL production and quinolone resistance from donors to transconjugants.

Genomic Characterization of MDR Escherichia coli Harboring blaOXA-48 on the IncL/M-type Plasmid Isolated from Blood Stream Infection.

Escherichia coli is responsible for a wide variety of community and hospital acquired extraintestinal infections, and the emergence of ESBL resistant isolates is a major clinical concern. In this study, we characterized the genomic attributes of an OXA-48 and CTX-M-3 producing E. coli EC-IMP153. Whole-genome initial assembly produced 146 contigs with a combined 5,504,170 bp in size and a G+C content of 50.5%. wgSNPs-based phylogenetic comparison with 36 publically available genomes was also performed. Comprehensive genomic analysis showed that EC-IMP153 belonged to sequence type ST-405 and harbored several resistance determinants including the ß-lactam resistance genes blaOXA-48, blaCTX-M-3, blaTEM-1B, blaOXA-1, and blaCMY-70, aminoglycoside fyuA and aac(3)IId, tetracycline tet(A) and tet(R), and fluoroquinolone gyrA, parC, and mfd resistance determinants. Plasmids with the following incompatibility groups were detected in silico and confirmed using PBRT: IncI1-α, IncL, IncW, Col (BS512), and IncF. To our knowledge this is the first in-depth genomic analysis of an OXA-48 producing E. coli ST-405 isolated from a patient in Lebanon and linked to a blood stream infection. Continuous monitoring is necessary to better understand the continued diffusion of such pathogens, especially in view of the population movements triggered by unrest in the Middle East.

Nationwide study of drug resistance among acid-fast bacilli positive pulmonary tuberculosis cases in Lebanon.

OBJECTIVE: To assess the prevalence of drug resistance among smear-positive sputum specimens from pulmonary tuberculosis (TB) cases in Lebanon. DESIGN: Between July 2002 and April 2004, 224 newly diagnosed TB cases and 21 previously treated TB cases were collected nationwide. Mycobacterium tuberculosis isolates were tested against isoniazid (INH), rifampicin (RMP), streptomycin (SM) and ethambutol (EMB) using the BACTEC-TB system. RESULTS: M. tuberculosis and non-tuberculous mycobacteria (NTM) isolates were recovered from 190 and 15 new cases, respectively, and from 16 and 1 previously treated cases, respectively. Overall drug resistance among new TB vs. previously treated TB cases was 19.5% and 75%, and for single drugs it was INH (12% vs. 63%), RMP (3% vs. 56%), SM (12% vs. 44%) and EMB (3% vs. 44%). The overall rate of multidrug resistance (MDR) was 5.8% (1% vs. 62.5%). The male:female ratio was 1.3:1; most were young adults. CONCLUSION: Relatively moderate single drug resistance and very low MDR rates were found among new TB cases, while among previously treated TB cases very high resistance and MDR resistance rates were detected. Such findings underline the need for ongoing stringent control measures to curb the spread of M. tuberculosis and its deleterious effects.

Rapid diagnosis of central nervous system brucellosis by ELISA.

The diagnosis of central nervous system (CNS) brucellosis was made by determining Brucella-specific IgG, IgM and IgA in cerebrospinal fluid (CSF) specimens, using an enzyme-linked immunosorbent assay (ELISA) method. A total of 68 CSF specimens including 10 from patients with brucellosis of the nervous system, 4 with Brucella infection but without CNS involvement, 38 with meningitis other than due to Brucella and 16 with no meningitis were studied. Of the 10 CSF specimens from patients with CNS brucellosis, Brucella-specific IgG was detected in all 10, IgM in 7 and IgA in 8. The 10 patients were also seropositive for anti-Brucella IgG and IgM, and 9 were seropositive for IgA. No Brucella-specific IgG, IgM or IgA was detected in the CSF of 4 patients with brucellosis but without CNS involvement, even though the blood of these patients had high titres of anti-Brucella IgG, IgM and IgA. In addition, none of the CSF specimens from the 38 patients with meningitis other than due to Brucella, or from the 16 patients without meningitis, had detectable anti-Brucella antibodies. This study indicates that the Brucella ELISA on CSF is a reliable, rapid, sensitive and specific assay in the diagnosis of CNS brucellosis.

ELISA versus routine tests in the diagnosis of patients with systemic and neurobrucellosis.

Sera from patients in different stages of brucellosis as well as sera and cerebrospinal fluid (CSF) from patients with central nervous system (CNS) brucellosis and controls, were tested by ELISA for Brucella-specific IgG, IgM and IgA. The results were compared with culture findings, micro-agglutination (MA), slide agglutination with Rose Bengal (RB), and Brucella melitensis stained antigens (SA). In sera of patients with acute brucellosis (296), ELISA was positive for IgM (100%), IgG (97%) and IgA (98%), and comparable results were found in sera of patients with subacute brucellosis (44): IgG (100%), IgM (86%) and IgA (100%). However, in patients with chronic brucellosis (40), IgG and IgA were consistently positive (100%) while IgM was only positive in 33% of their sera. The MA and RB showed similar results, being more positive in patients with acute (98%) and subacute (84%) than in chronic (61%) brucellosis. The SA and culture showed significantly lower positive results. In the CSF of patients with CNS brucellosis (45), ELISA was positive in 100%, 20% and 85% for IgG, IgM and IgA, respectively, compared to 13% positive by culture, 25% by MA and 22% by RB. ELISA was negative in the CSF specimens from patients with brucellosis without CNS involvement (66), or meningitis other than Brucella (62), and no meningitis (144). Thus, ELISA with its IgG, IgM and IgA profiles is the test of choice in the diagnosis of patients with brucellosis, especially those with chronic or CNS infection.

Neurobrucellosis in children.

Reports on nervous system involvement in brucellosis are rare in children. We report nine children with neurobrucellosis. The clinical presentation included meningitis in six patients, one with encephalitis, one with meningoencephalitis and one with meningomyeloencephalitis. The blood from all patients showed elevation in Brucella microagglutination test titers (greater than or equal to 1:640) and in Brucella-specific enzyme-linked immunosorbent assay for IgM (greater than or equal to 1:800), IgG (greater than or equal to 1:800) and IgA (greater than or equal to 1:800) antibodies. Brucella melitensis was recovered from the blood in five patients and from the cerebrospinal fluid in three patients. The cerebrospinal fluid showed lymphocytic pleocytosis in eight patients with elevated protein in three, decreased glucose in four and a Brucella microagglutination test titer of greater than or equal to 1:80 in all. Treatment with a combination of oral tetracyclines with intramuscular streptomycin was successful in five patients, rifampin with streptomycin in two, tetracycline with rifampin in one and tetracycline, rifampin and streptomycin in one. No relapses, mortality or sequelae occurred in our patients.

A multicenter therapeutic study of 1100 children with brucellosis.

A 6-year multicenter therapeutic study was performed on 1100 children with brucellosis in order to compare several antibiotic combinations and duration of treatment. The patients were randomized to receive oral therapy with oxytetracycline, doxycycline, rifampin and trimethoprim-sulfamethoxazole (TMP/SMX) either alone or in combination with each other or combined with streptomycin or gentamicin injections. The patients were also randomized into three groups based on the duration of oral therapy: 500 patients were treated for 3 weeks; 350 for 5 weeks; and 250 for 8 weeks. When intramuscular aminoglycosides were used, streptomycin was given for 2 weeks and gentamicin for 5 days. In oral monotherapy oxytetracycline, doxycycline and rifampin showed comparable results with low relapse rates (less than or equal to 9%) and no statistically significant differences were found among 3-, 5- or 8-week durations of therapy. TMP/SMX alone showed an unacceptably high relapse rate (30%) with all durations of therapy. In combined oral therapy rifampin plus oxytetracycline, rifampin plus TMP/SMX and oxytetracycline plus TMP/SMX showed comparable results with low relapse rates ranging from 4 to 8% in patients receiving therapy for 3 or 5 weeks, no relapses occurred in patients treated for 8 weeks. When oral monotherapy was combined with either streptomycin or gentamicin, very few relapses were seen, irrespective of the duration of treatment.(ABSTRACT TRUNCATED AT 250 WORDS)

Clinical laboratory evaluation of a bacteriuria detection device for urine screening.

The BAC-T-SCREEN (BTS) (Marion Laboratories, Inc., Kansas City, MO) is a 2 1/2-minute urine screen designed to detect culture-negative specimens. A total of 1,609 urine specimens were tested by the BTS, and results were compared with quantitative culture methods. One hundred and forty-eight (9.2%) specimens were not screened successfully by the BTS because they contained interfering pigments or clogged the test filters. A total of 1,461 specimens were tested successfully. The sensitivity, specificity, positive predictive value, and negative predictive value for specimens containing greater than or equal to 10(5) CFU/mL were 98.0, 72.2, 57.3, and 99.0%, respectively. These values for specimens containing greater than or equal to 10(4) CFU/mL were 93.2, 77.2, 69.2, and 95.5%, respectively.

Comparison of the carcinoembryonic antigen levels by dialysis and sephadex column methods.

Duplicate plasma samples from 64 human donors were tested and compared for the levels of carcinoembryonic antigen (CEA) by the conventional dialysis and sephadex column methods. Results from the column method were similar to those from the dialysis method, with a correlation coefficient of 0.9959. In addition, the assay time by the sephadex column was only four to five hours, as compared with 18 to 24 hours for the dialysis procedure. The potential usefulness in substituting the sephadex column for the dialysis method in CEA determinations is discussed.

Antimicrobial susceptibility patterns of bacterial isolates at the American University Medical Center in Lebanon.

In Lebanon, knowledge of the prevailing pattern of bacterial resistance to antimicrobial agents has been limited, particularly because of 15 years of civil strife. Thus, the current study was conducted to determine the antimicrobial susceptibility patterns of nonselected bacterial isolates recovered from recent clinical specimens, using the standardized disk agar diffusion technique. A total of 5216 isolates (1443 Gram positive and 3773 Gram negative) were examined. Over 92% of Staphylococcus aureus and coagulase-negative staphylococci (CNS) were resistant to penicillins. Methicillin resistance was more frequently noted among CNS (28%) compared with S. aureus (18%). For the pneumococci, 27% of the isolates were resistant to penicillin G. High but variable rates of multidrug resistance were encountered among Acinetobacter spp., Pseudomonas spp., Serratia spp., Citrobacter spp., and Enterobacter spp. Ampicillin resistance was detected in 65% of Escherichia coli and in 20% of Haemophilus influenzae isolates. Although one resistant Salmonella typhi strain was observed, 17% of other Salmonella spp. and 60% of Shigella spp. proved to be resistant to ampicillin, chloramphenicol, and cotrimoxazole. Among Vibrio cholerae isolates, high resistance to tetracycline (71%) and trimethoprim-sulfamethoxazole (94%) was observed. The overall antimicrobial resistance rates in Lebanon seem to fall between figures reported from the Arabian Gulf countries (higher) and those from medical centers in the United States (lower).

Characterization of rpoB mutations in rifampin-resistant Mycobacterium tuberculosis isolates from the Middle East.

The nature and frequency of mutations in the rpoB gene of rifampin-resistant clinical Mycobacterium tuberculosis isolates vary considerably according to geographical locations. There is no information on the prevalence of specific mutations in clinical M. tuberculosis strains isolated from patients in Middle-Eastern countries. In this study, 13 rifampin-resistant and 6 susceptible clinical M. tuberculosis isolates were tested for identification and characterization of mutations in the rpoB gene by INNO-LiPA Rif. TB kit and DNA sequencing of the PCR amplified target DNA. The kit identified all six susceptible strains as rifampin-sensitive and the DNA sequence of the amplified rpoB gene in the target region matched perfectly with the wild-type sequence. The kit identified 12 resistant isolates as rifampin-resistant with specific detection of mutations in 8 isolates while one of the rifampin-resistant strain was identified as rifampin-susceptible. DNA sequencing confirmed these results and, in addition, led to the specific detection of mutations in 4 rifampin-resistant isolates in which specific base changes within the target region could not be determined by the INNO-LiPA Rif. TB kit. The majority (8 of 13) of resistant isolates involved base changes at codon 531 of the rpoB gene. Mutations at codon position 531 within the rpoB gene have also been reported in majority of rifampin-resistant strains from Greece and St. Petersburg, Russia but not from other geographical locations.

Improved detection of mycobacterial antigens in clinical specimens by combined enzyme-linked immunosorbent assay.

Three types of antibodies against cellular and secretory-excretory protein antigens were simultaneously used for the direct detection of mycobacterial antigens in sputum and cerebrospinal fluid (CSF) specimens, using enzyme-linked immunosorbent assay (ELISA). The antibodies consisted of in-house raised and prepared anti-whole-cell, heat-killed, and sonicated Mycobacterium tuberculosis, anti-secretory-excretory protein extract of bacilli Calmette-Guerin (BCG) strain, and commercially available anti-BCG. Sputum specimens comprised 24 smear positive, culture positive, and 47 smear-negative, culture positive (SNCP), from patients with pulmonary tuberculosis, as well as 45 smear-negative, culture-negative (SNCN) control samples. The CSF specimens included 18 SNCPs from patients with tuberculous meningitis and 18 SNCN controls. The sensitivity of the individual tests for sputum and CSF specimens ranged from 70% to 79% and 72% to 89%, respectively, whereas in the combined tests it reached 86%-96% for sputum specimens and 100% for CSF specimens. The specificity of ELISAs for sputum specimens was lower in the combined (73%-87%) than in the individual (87%-98%) tests, whereas for CSF specimens it was 100% in all tests. Thus, the combined ELISA approach for mycobacterial antigen detection provides a rapid and reliable laboratory adjunct in the diagnosis of patients with tuberculosis.

Campylobacter jejuni: unusual cause of cholecystitis with lithiasis. Case report and literature review.

A 51-year-old man presented with acute cholecystitis and the routine intraoperative culture of the bile grew Campylobacter jejuni. The patient was cured by laparoscopic cholecystectomy without specific antimicrobial treatment. Cholecystitis owing to Campylobacter spp. could be missed because a culture for Campylobacter is not routinely requested nor is it cost effective to look for it in bile or gallbladder specimens. Moreover, the fastidious nature of these bacteria dictates against their recovery in routine culture. Because this is a rare infection at this site, a review of the literature on this infection is included.

Campylobacter fetus pericarditis in a patient with beta-thalassemia: case report and review of the literature.

A case of pericardial effusion due to Campylobacter fetus in a patient with thalassemia is presented. The patient failed to respond to ceftriaxone and clarithromycin despite in vitro susceptibility, but improved after pericardiectomy and ampicillin. Pericarditis due to C. fetus has rarely been reported. A high index of suspicion is essential to recognise this organism, because of its special microbiological characteristics.

Drug resistance among Mycobacterium tuberculosis isolates in Lebanon.

OBJECTIVE: To determine the prevalence and patterns of drug resistance among Mycobacterium tuberculosis isolates recovered from tuberculosis (TB) cases in Lebanon. DESIGN: A total of 96 isolates were collected from the same number of TB cases between October 1994 and December 1995. These isolates were obtained from cases with newly diagnosed (81.3%) and previously treated (18.7%) cases of TB, and tested against isoniazid (INH), rifampicin (RIF), streptomycin (STM) and ethambutol (ETH), using the BACTEC-TB susceptibility procedure and system. RESULTS: The male to female ratio was 2:1 and the mean ages of males and females were almost similar, 34.1 and 32.7 years, respectively. Resistance to one or more drugs was found in 25 of 96 (26%) isolates. The overall percentages of single drug resistance against INH, RIF, STM and ETH were 23.9%, 12.5%, 7.3% and 3.1%, respectively. These percentages were higher, for all drugs, in isolates recovered from previously treated compared to new cases of TB: INH (50% vs 17.9%), RIF (33.3% vs 7.7%), STM (22.2% vs 3.8%) and ETH (11.1% vs 1.3%). Of the 25 resistant isolates, 11 were resistant to one drug only (10 to INH and 1 to STM), 10 were resistant to two drugs (7 to INH and RIF, 2 to INH and STM, 1 to STM and RIF), 2 were resistant to three drugs (1 to INH, RIF and ETH, 1 to INH, RIF and STM) and 2 were resistant to the four tested drugs. CONCLUSION: These data show that M. tuberculosis isolates in Lebanon have high rates of single and multidrug resistance, and speaks for the need to establish surveillance and monitoring programs in this country as part of the global effort to control TB.