Evaluation of a Molecular Test for Detection of Mycobacterium tuberculosis Isolates Resistant to Rifampicin and Isoniazid.

BACKGROUND: Multidrug-resistant tuberculosis (MDR-TB) is increasing worldwide and is a major cause of death in many countries. It has become a major challenge for national tuberculosis control programs. Therefore, rapid identification of MDR strains of Mycobacterium tuberculosis and monitoring of their transmission could contribute significantly to the fight against tuberculosis. The GenoType MTBDRplus assay has been recommended by the World Health Organization to identify rifampicin (RIF)- and isoniazid (INH)-resistant M. Tuberculosis isolates. The objectives of this study were to evaluate the performance of the GenoType MTBDRplus test in the detection of rifampicin and isoniazid resistance of M. tuberculosis isolates in a Moroccan hospital and then to determine the frequency of mutations associated with resistance to these two major anti-tuberculosis drugs. METHODS: This is a retrospective study conducted at the bacteriology department of the Mohammed V military hospital over a period of one year from 01/01/2018 to 12/31/2019. A total of 92 isolates of M. tuberculosis from pulmonary and extra-pulmonary specimens were evaluated for drug susceptibility by MGIT™ 960 AST system and compared to the GenoType MTBDRplus assay. The MGIT™ 960 AST system was used as the gold standard for the evaluation of the GenoType MTBDRplus assay. RESULTS: Sensitivity and specificity of the GenoType MTBDRplus assay for the detection of RIF-resistant M. tuberculosis isolates were 83.33% and 100%, respectively. Its sensitivity and specificity for the detection of INH-resistant M. tuberculosis were 88.23% and 100% respectively. The concordances of the GenoType MTBDRplus assay and the MGIT™ 960 AST system for the detection of sensitivity to RIF and INH were 99% (1/92) and 98% (2/92), respectively. Among the five RIF-resistant isolates, the MUT3 mutation in the rpoB gene (codon S531L mutation) was present in 80% of isolates, whereas mutations in the rpoB MUT1 gene were present in only one (20%) RIF-resistant isolate. INH resistance was detected in 15 isolates, of which nine isolates (60%) had specific mutations of the katG gene (codon S315T1) and conferred a high level of resistance to INH. CONCLUSIONS: The results of this study have shown that the GenoType MTBDRplus test has a high sensitivity and specificity for the detection of resistance to RIF and INH.

Breast tuberculosis: A forgotten diagnosis.

Breast tuberculosis is a rare entity even in endemic countries. It is often considered as a diagnostic conundrum given the non-specific clinical and imaging characteristics. Therefore, the definitive diagnosis is based on the identification of bacilli by microbiological or histopathological examination. We report the case of a 52-year-old woman, with a 2-month history of a painful lump of the left breast. The imaging features were consistent with a breast abscess. The purulent collection was aspirated and a tuberculous mammary abscess was diagnosed by molecular biology (GeneXpert). Through this observation, we discuss the clinical, radiological and biological signs by highlighting the contribution of molecular biology in the rapid management of this rare pathology.

Shewanella putrefaciens: A cause of bacteremia not to neglect.

Shewanella putrefaciens is a Gram-negative bacillus and marine pathogen that rarely causes disease in humans. We report the first Moroccan case of multidrug-resistant Shewanella putrefaciens bacteremia and describe the bacteriological, clinical, and antibiogram characteristics of this isolate, which was repeatedly isolated from the blood of a 66-year-old hypertensive man who underwent femoral coronary angiography after a myocardial infarction.

The occurrence of a multidrug-resistant tuberculous retropharyngeal abscess in an immunocompetent patient: A case report.

Retropharyngeal abscess is an uncommon location of tuberculosis (TB). In this report, we describe a multidrug-resistant tuberculous retropharyngeal abscess in a 21-year-old female patient who was treated for lymph node TB for one year. CT scan revealed a large retropharyngeal abscess that was aspirated intraorally under local anesthesia. The diagnosis of TB was retained by molecular and histological study. GeneXpert MTB/ RIF (Cepheid, Sunnyvale, CA, USA),performed on the pus, showed rifampicin resistance and a first- and second-line drug resistance test using Genotype MTBDRplus VER.2 and MTBDRsl VER.1 (Hain Lifescience GmbH, Nehren, Germany) showed TB highly resistant to rifampicin, isoniazid, and aminoglycosides. Treatment is primarily medical as it combines specific antituberculous antibiotics, and aspiration for drainage of the abscess. Our patient was put on long-term 2nd line anti-TB treatment.

A Case of Colonic Tuberculosis Revealed by Polymerase Chain Reaction.

BACKGROUND: The authors report a case of tumor-like colonic tuberculosis revealed by PCR in a 32-year-old patient with a low-level peritoneal effusion on CT scan with negative histological study on colonic biopsy. METHODS: The colonic biopsy received at the laboratory after grinding in a porcelain mortar, was the object of a molecular study by GeneXpert MT/RIF (Cepheid, Sunnyvale, CA, USA) using the automated real-time PCR technique and a conventional study based on Ziehl-Nielsen staining and culture on Lowenstein-Jensen® solid medium (LJ) and Mycobacteria Growth Indicator Tube (MGIT®) liquid medium. RESULTS: The patient was a 32-year-old male without any personal or family history of tuberculosis and without signs of tuberculosis impregnation. He had a story of ingestion of non-pasteurized dairy products including milk and cheese. For 45 days he had constipation with abdominal pain and feeling of heaviness. Physical examination of the patient revealed abdominal tenderness without adenopathy. The laboratory workup showed a normal blood count, CRP, liver and kidney function tests. The HIV test was negative. Medical imaging revealed a low-level peritoneal effusion that could not be punctured. Colonoscopy showed a thickening of the colon. The colonic biopsy, after crushing and sonication, was searched for the Mycobacterium tuberculosis complex by both molecular biology and conventional methods. Molecular research by GeneXpert MTB/RIF (Cepheid, Sunnyvale, CA, USA) using the automated real-time PCR technique, revealed the presence of the Mycobacterium tuberculosis complex without detection of rifampicin resistance. On the other hand, the direct examination after special Ziehl-Nielsen staining was positive (Figure 2) and the cultures on Lowenstein-Jensen® solid medium (LJ) and Mycobacteria Growth Indicator Tube (MGIT®) liquid medium were also positive after two and three weeks, confirming the molecular diagnosis. The histology study showed moderate non-specific chronic colitis with no histological arguments for tuberculosis or malignancy. The patient was placed on curative tuberculosis treatment according to the national protocol, with a favorable clinical-radiological course. CONCLUSIONS: Colonic tuberculosis is a disease that may mimic many other diseases; therefore, a correct approach is necessary for the correct diagnosis and treatment.

Infective endocarditis caused by Escherichia coli of a native mitral valve.

Escherichia coli is a rare cause of infectious endocarditis. We report a clinical case of E. coli endocarditis of a native mitral valve in a young 26-year-old woman with a recurrent urinary tract infection who had a high fever for one week despite probabilistic treatment with amoxcillin-clavulanic acid 3 g per day. The patient was successfully treated with antibiotics and recovered without surgery.

Whole-Genome Sequencing of Two Moroccan Mycobacterium tuberculosis Strains.

Mycobacterium tuberculosis is known to cause pulmonary and extrapulmonary tuberculosis. In Morocco, the spread of multidrug-resistant (MDR) tuberculosis (TB) has become a major challenge. Here, we announce the draft genome sequences of two Mycobacterium tuberculosis strains, MTB1 and MTB2, isolated from patients with pulmonary tuberculosis in Morocco, to describe variants associated with drug resistance.

Septic arthritis of the ankle: Do not forget Pasteurella pneumotropica.

Pasteurella pneumotropica is an important bacterial pathogen in both animals and humans. Most reported Pasteurella infections in humans involve skin and soft tissues, often after an animal bite, scratch, or lick to an open wound. We report a case of septic arthritis with Pasteurella pneumotropica in a diabetic and cardiopathic patient who was the victim of a rat bite in the street, with a good evolution after medical and surgical treatment.

Cytological examination of cerebrospinal fluid: Sysmex UF-1000i versus optical microscopy.

We evaluated the body fluid module on Sysmex UF-1000i (UF-1000i-BF) for analysis of white blood cell (WBC) and red blood cell (RBC) in cerebrospinal fluid. We collected 93 cerebrospinal fluid samples and compared the results of the UF-1000i-BF mode with the Fast-Read 102 disposable counting cell. Results shows a good correlation between the UF-1000i and the microscopic examination. The concordance percentage is 99.06% for white blood cells and 85.18% for red blood cells. The UF-1000i-BF mode offers rapid and reliable total WBC and RBC counts for initial screening of cerebrospinal fluid, and can improve the workflow in a routine laboratory.

Serious phlegmonous lesion of the hand following an injury by vegetal thorn: Never forget Pasteurella multocida!

Pasteurella multocida can cause serious infections after dog or cat bite. We report here a rare case of hand infection caused by P. multocida consecutive to an injury by a thorn of the prickly pear. It caused an amputation of the distal phalanx of the thumb in a trisomic patient. It is about a 27-year-old man who was admitted to the hospital with swelling and intense pain of the left hand. He reported a sting by a thorn of prickly pear 15 days before. The patient was admitted to proceed with operative irrigation and debridement. The pus was collected for microbiological examination. Microscopic examination after Gram staining revealed small Gram-negative coccobacilli, associated to polymorphonuclear reaction. Culture have objectivated Pasteurella multocida. The isolated strain was susceptible to betalactamins. Patient was treated with ampicillin. Well-conducted antibiotics and repetitive local cares have not prevented local lesions from progressing to necrosis of the soft parts of the thumb and osteitis of the distal phalanx of the thumb. The patient underwent a necrosectomy and an amputation of the distal phalanx. Ampicillin was replaced by amoxicillin/clavulanic acid and after 15 days, progression was clinically and microbiologically favorable. In the case we report, since the patient does not report any exposure or contact with animals, the thorn prick is the source of infection. It was contaminated from the animal reservoir. Taking into account the monomicrobism of the infection, treatment with aminopenicillins was sufficient. Our propositus came to the hospital 15 days after the inoculation of the bacterium. This duration appears to be very late in relation to the acute character of pasteurellosis. This was probably the main reason why the local infection evolved towards osteoarticular complications. That's why, we should consider Pasteurella multocida in case of infection by inoculation, even in the absence of contact with the animals.

Annotated Whole-Genome Shotgun Sequence of Multidrug-Resistant Mycobacterium tuberculosis MTB13_M Isolated from Morocco.

Here, we describe the annotated genome sequence of Mycobacterium tuberculosis MTB13_M. The organism was isolated from a sputum sample in Morocco.

[Saccharomyces cerevisiae invasive infection: The first reported case in Morocco]. / Infection invasive à Saccharomyces cerevisiae : le premier cas rapporté au Maroc.

Saccharomyces cerevisiae is a cosmopolitan yeast, widely used in agro-alimentary and pharmaceutical industry. Its impact in human pathology is rare, but maybe still underestimated compared to the real situation. This yeast is currently considered as an emerging and opportunistic pathogen. Risk factors are immunosuppression and intravascular device carrying. Fungemias are the most frequent clinical forms. We report the first case of S. cerevisiae invasive infection described in Morocco, and to propose a review of the literature cases of S. cerevisiae infections described worldwide. A 77-year-old patient, with no notable medical history, who was hospitalized for a upper gastrointestinal stenosis secondary to impassable metastatic gastric tumor. Its history was marked by the onset of septic shock, with S. cerevisiae in his urine and in his blood, with arguments for confirmation of invasion: the presence of several risk factors in the patient, positive direct microbiological examination, abundant and exclusive culture of S. cerevisiae from clinical samples. Species identification was confirmed by the study of biochemical characteristics of the isolated yeast. Confirmation of S. cerevisiae infection requires a clinical suspicion in patients with risk factors, but also a correct microbiological diagnosis.

Postoperative mediastinitis due to Candida tropicalis: first reported case in Morocco.

Mediastinitis is a rare and serious nosocomial complication of cardiac surgery. It is estimated at less than 2% of cases of median sternotomy. We report the case of a postoperative mediastinitis due to Candida tropicalis. A 9-month-old baby was operated for complete repair of tetralogy of Fallot in which we isolated C. tropicalis from sternal purulent fluid and blood culture. The child did not survive, despite the initiation of antifungal therapy. The management of this type of infection requires an early diagnosis and an appropriate prolonged treatment, associated with effective preventive measures.

An 8-year survey of strains identified in blood cultures in a clinical haematology unit.

The aim of our study was to determine the epidemiological profile and the antibiotic susceptibility of bacteria and fungi identified from blood cultures in the patients of the clinical haematology unit. A retrospective study was carried out over an 8-year period (2003-2010) in the clinical haematology unit of the Percy Military Medical Center. During this period, we collected 723 isolates: Gram-negative bacilli (70.8%) and Gram-positive cocci (18.7%). The four most commonly isolated species were Escherichia coli (18.5%), Pseudomonas aeruginosa (14.8%), Stenotrophomonas maltophilia (6.2%) and Staphylococcus epidermidis (5.4%). The rate of methicillin-resistant Staphylococcus aureus was 6.45% and that of coagulase-negative staphylococci 61.2%. No resistance to glycopeptides was observed. In E. coli, as in the Klebsiella-Enterobacter-Serratia group, a 27% resistance to fluoroquinolones was observed. Concerning P. aeruginosa, the phenotypes were distributed over penicillinase (23.4%) and cephalosporinase (13.1% were resistant to ceftazidime). The impermeability rate of imipenem was 9.3%. The aggressiveness and duration of haematological treatments explains why infections remain one of the main complications of neutropenia. The emergence of new or unusual bacteria is highly likely. Antibiotic selective pressure and long periods of hospitalization could explain the emergence of multiresistant bacteria. As a consequence, epidemiological surveillance is indispensable.

In Vitro Activities of Ertapenem and Imipenem against Clinical Extended Spectrum Beta-Lactamase-Producing Enterobacteriaceae Collected in Military Teaching Hospital Mohammed V of Rabat.

Objective. To study the sensitivity level of extended spectrum beta-lactamase-producing Enterobacteriaceae to Carbapenems (Imipenem, Ertapenem) marketed in Morocco and discusses the place of Ertapenem in the treatment of extended spectrum-beta-lactamase-producing. Materials and Methods. A retrospective study of 110 extended spectrum beta-lactamase-producing Enterobacteriaceae. Isolates obtained from blood cultures, superficial and deep pus, and catheters were conducted. The minimum inhibitory concentrations of Imipenem and Ertapenem were done by the E-test. The modified Hodge test was conducted for resistant or intermediate strains. Results. 99.1% of isolates were susceptible to Imipenem. For Ertapenem, 4 were resistant and 4 intermediate. The modified Hodge test was positive for all 08 isolates. A minimum inhibitory concentration comparison of K. pneumoniae, E. cloacae, and E. coli for Imipenem has noted a significant difference between E. cloacae on one hand and E. coli, K. pneumoniae on the other hand (P < 0.01). No significant difference was noted for minimum inhibitory concentration of Ertapenem. Conclusion. Our results confirm in vitro effectiveness of Ertapenem against extended spectrum beta-lactamase-producing Enterobacteriaceae as reported elsewhere. However, the emergence of resistance to Carbapenems revealed by production of carbapenemases in this study confirmed a necessary bacteriological documented infection before using Ertapenem.

[Nodular liver lesions with fever in a Moroccan man: hepatic brucelloma]. / Nodules hépatiques fébriles chez un marocain.

Hepatic brucelloma is an exceptional localization in brucellosis. The purpose of this report is to describe an uncommon case involving a 42-year-old man hospitalized for febrile hepatic cytolysis. Diagnosis was established based on positive rose bengal test results, positive blood culture, hypoechogenic masses on ultrasound, and hypodense enhancing masses on CT scan. Hepatic brucelloma is a focal suppurative lesion occurring after undetected acute brucellosis or undertreated brucellosis. Diagnosis is based on the association of imaging showing characteristic features (hepatic calcifications) and on positive blood culture and serology. First-line treatment should consist of doxycyclin and rifampicin for 2 to 12 months. If medical treatment fails, surgical drainage should be performed.

[Blood isolates epidemiology in a clinical haematology department]. / Epidémiologie des isolats d'hémocultures: expérience d'un service d'hématologie clinique.

Cancer chemotherapy is responsible for infections by decreasing the phagocytosis and chemotaxis of polymorphonuclear. We conducted a retrospective analysis during the period from 18/10/2006 to 21/05/2008, on all bacteria isolated from blood cultures performed in the department of clinical hematology at the hospital military instruction Mohamed V. One hundred and sixty two blood isolates were selected; Gram positive cocci (CGP) accounted for 60.34% and Gram negative bacilli (GNB) for 24.14%. Coagulase negative staphylococci (SNA) and S. aureus presented a resistance to methicilline respectively 54.55% and 22.22%. Prevalence of Gram positive cocci is consistent with the results of the EORTC (International Antimicrobial Therapy Cooperative Group). Analysis of resistance patterns of all species, except for staphylococci, showed phenotypes essentially community, sometimes wild. In conclusion probabilistic antibiotic treatement of bacteraemia in the haematology department should focus among other staphylococci resistant to methicilline.

[Antibiotic susceptibility of Staphylococcus aureus strains isolated in two university hospitals in Rabat, Morocco]. / Sensibilité aux antibiotiques des souches de Staphylocoques aureus isolées dans deux hôpitaux universitaires à Rabat, Maroc.

OBJECTIVES: The aim of this study was to assess the in vitro activity of several antimicrobial agents against Staphylococcus aureus (S. aureus). METHOD: This 2 year study was made in two Moroccan teaching hospitals. Four hundred and sixty-one non-repetitive clinical S. aureus strains were isolated and collected from various samples collected in several units between March 2006 and March 2008. The susceptibility of strains was determined by the agar disk diffusion method. RESULTS: The rate of methicillin resistance was 19.3% for S. aureus isolates. 53.93% of S. aureus strains were resistant to gentamycin, and all strains were susceptible to glycopeptides. CONCLUSION: The rate of MRSA was high. Resistance to methicillin is often associated with resistance to gentamycin and fluoroquinolones. Vancomycin and teicoplanin were still effective on S. aureus in the two university hospitals.