P.O. Box 131375, Bryanston, 2074 Ground Floor, Block 5 Bryanston Gate, 170 Curzon Road Bryanston, Johannesburg, South Africa www.thistle.co.za Tel: +27 (011) 463 3260 Fax: +27 (011) 463 3036 Fax to Email: + 27 (0) 86-557-2232 e-mail : [email protected] Please read this section first The HPCSA and the Med Tech Society have confirmed that this clinical case study, plus your routine review of your EQA reports from Thistle QA, should be documented as a “Journal Club” activity. This means that you must record those attending for CEU purposes. Thistle will not issue a certificate to cover these activities, nor send out “correct” answers to the CEU questions at the end of this case study. The Thistle QA CEU No is: MT-2015/009. Each attendee should claim THREE CEU points for completing this Quality Control Journal Club exercise, and retain a copy of the relevant Thistle QA Participation Certificate as proof of registration on a Thistle QA EQA. MICROBIOLOGY LEGEND CYCLE 37 ORGANISM 5 Morganella morganii Historical identification Morganella morganii was first described by a British bacteriologist H. de R. Morgan in 1906 as Morgan's bacillus. Morgan isolated the bacterium from stools of infants who were noted to have had "summer diarrhea". Later in 1919, Winslow et al. named Morgan's bacillus, Bacillus morganii. In 1936, though, Rauss renamed B. morganii as Proteus morganii. Fulton, in 1943, showed that B. columbensis and P. morganii were the same and defined the genus Morganella, due to the DNA-DNA hybridization. However in 1962, a review article by Ewing reported that M. columbensis had been re-identified as Escherichia coli, therefore removing that organism from the genus Morganella. Currently, Morganella contains only a single species, M. morganii, with 2 subspecies, morganii and sibonii. M. morganii is a member of the tribe Proteeae (normal fecal flora that often causes infection in patients whose normal flora have been disturbed by antibiotic therapy) of the family Enterobacteriaceae. M. morganii previously classified under the genus Proteus as Proteus morganii is a species of Gram-negative bacteria. It has a commensal relationship within the intestinal tracts of humans, mammals, and reptiles as normal flora. M. morganii is facultatively anaerobic and oxidase-negative. Its colonies appear off-white and opaque in colour, when grown on agar plates. M. morganii cells are straight rods, about 0.6 - 0.7 µm in diameter and 1.0 - 1.7 µm in length. This organism moves by way of peritrichous flagella, but some strains do not form flagella at 30°C. M. morganii can produce the enzyme catalase, so is able to convert hydrogen peroxide to water and oxygen. This is a common enzyme found in most living organisms. In addition, it is indole test-positive representing this organism can split tryptophan to indole, pyruvate, and ammonia. Methyl red, an indicator dye that turns red in acidic solutions, tests positive in M. morganii. M. morganii has been regarded as a harmless opportunistic pathogen and is a rare cause of severe invasive disease. It accounts for less than 1% of nosocomial infections. M. morganii has been reported as a cause of urinary tract infections, nosocomial surgical wound infections, peritonitis, central nervous system infection, endophthalmitis, pneumonia, chorioamnionitis, neonatal sepsis, pyomyositis, necrotizing fasciitis, and arthritis. Numerous cases of nosocomial infection have been described, usually as postsurgical wound infections or urinary tract infections. Patients in whom bacteremia develops are typically immunocompromised, diabetic, or elderly, or have at least one serious underlying disease. Thistle QA is a SANAS accredited organisation, No: PTS0001 Accredited to ISO 17043 Certificate available on request or at www.sanas.co.za Page 1 of 3 P.O. Box 131375, Bryanston, 2074 Ground Floor, Block 5 Bryanston Gate, 170 Curzon Road Bryanston, Johannesburg, South Africa www.thistle.co.za Tel: +27 (011) 463 3260 Fax: +27 (011) 463 3036 Fax to Email: + 27 (0) 86-557-2232 e-mail : [email protected] Clinical Presentation Urinary tract infections: M morganii is commonly recovered from urine cultures in patients with long- term indwelling urinary catheters. Perinatal infections: M morganii has been associated with perinatal infection. Snakebites: M morganii is commonly found in the mouths of snakes. As a result, it is one of the organisms recovered most often from snakebite infections. Infections in people with AIDS Bacteremia Laboratory Studies Identification of M morganii is made by recovery of small oxidase-negative catalase and indole-positive gram-negative rods on blood agar or MacConkey agar. M morganii ferments glucose and mannose but not lactose. M morganii is motile, facultatively anaerobic, and nonencapsulated, and it hydrolyzes urease and reduces nitrates. Unlike Proteus species, swarming does not occur. M morganii urinary tract infections are often associated with an alkaline urine pH. M. morganii Gram stain of blood culture. M. morganii grown on blood agar Thistle QA is a SANAS accredited organisation, No: PTS0001 Accredited to ISO 17043 Certificate available on request or at www.sanas.co.za Page 2 of 3 P.O. Box 131375, Bryanston, 2074 Ground Floor, Block 5 Bryanston Gate, 170 Curzon Road Bryanston, Johannesburg, South Africa www.thistle.co.za Tel: +27 (011) 463 3260 Fax: +27 (011) 463 3036 Fax to Email: + 27 (0) 86-557-2232 e-mail : [email protected] Treatment and Antibiotic Resistance Treatment of M. morganii infections may include: Ticarcillin Piperacillin Ciprofloxacin Third-generation and fourth-generation cephalosporins However, some M. morganii strains are resistant to penicillin, ampicillin/sulbactam, oxacillin, first -generation and second-generation cephalosporins, macrolides, lincosamides, fosfomycin, colistin, and polymyxin B. The emergence of highly resistant strains of M. morganii have been associated with use of third-generation cephalosporins. References 1. CNS infectionshttp://emedicine.medscape.com/article/222443 2. http://en.wikipedia.org/wiki/Morganella_morganii Questions 1. Discuss the morphological characteristics of M. morganii. 2. Discuss the role of M. morganii in disease. 3. Discuss the lab diagnosis of M. morganii. \ Thistle QA is a SANAS accredited organisation, No: PTS0001 Accredited to ISO 17043 Certificate available on request or at www.sanas.co.za Page 3 of 3 .