Staphylococcus aureus is a common and often serious human pathogen accounting for about a fifth of all cases of bacteraemia with an associated mortality of up to 50%. This review summarizes the aspects of S. aureus bacteraemia that are relevant in a Lao context, including the antibiotic susceptibility patterns seen at Mahosot Hospital, Vientiane over the past 11 years and provides guidance and rationale for clinical management. In the Lao PDR it is the third commonest cause of bacteraemia and the leading cause of skin and soft-tissue infection. Mahosot Hospital has seen almost 200 cases and antibiotic susceptibility testing shows that a significant proportion of isolates are tetracycline and erythromycin resistant. Methicillin-resistance remains very rare, though this is unlikely to continue. Key risk factors for S. aureus disease in financially-poor settings include surgical procedures and previous antibiotic exposure. The identification and removal or drainage of a focus of infection is a key part of the management strategy. Transthoracic echocardiography (TTE) is advised for all patients, where this technique is accessible, and consideration should be given to repeating this test or performing a transoesophageal echocardiogram for patients with a negative TTE, but with a high index of suspicion for infective endocarditis. Treatment with a !-lactam antibiotic (preferably cloxacillin), for 2 weeks in uncomplicated disease and 4 to 6 weeks in complicated disease, is essential to provide cure and prevent relapse. An oral switch may be required, though this should take place only if the patient has been afebrile for 48 hours and has no ongoing complications requiring intervention. Copyright: ∀ 2012 Elliot et al. This is an open-access article distributed under the terms of the Creative Commons Attribution Licence, which permits unrestricted use, distribution, and reproduction in any medium, provided the original author and source are credited.

The effect of lemon slices, as well as ascorbic and citric acid impregnated paper discs, on the growth of ten non-typhoidal Salmonella, six Citrobacter freundii and four Proteus mirabilis species on Desoxycholate Hydrogen Sulfide Lactose (DHL) agar were examined in comparison to controls without fruit slices or paper discs applied. After 24 h incubation, thick black rings were observed around fruit slices and impregnated discs growing on non-typhoidal Salmonella serovars and not around the other species. We named this the “MY Phenomenon”. We propose that the phenomenon can be used as a rapid, simple and inexpensive screening test that distinguishes non-typhoidal Salmonella species from other enterobacteriaceae in stool samples.

Tuberculosis (TB) is an infectious disease commonly found in both developing and developed countries. Tuberculosis meningitis (TBM) is a serious central nervous system infection with a high mortality rate despite anti-TB drug treatment and is associated with HIV/AIDS. The diagnosis of TBM is difficult since the clinical aspects of the disease are similar to other central nervous system infections, examination for AFB in cerebrospinal fluid (CSF) stained with Ziehl-Neelsen is not sensitive and culture of Mycobacterium tuberculosis from CSF takes too long to influence initial therapy. Delayed diagnosis and treatment of TBM results in high mortality and disability. We report a Lao patient who had pulmonary TB in combination with TBM (confirmed by positive AFB in a sputum examination and a positive culture of Mycobacterium tuberculosis in the CSF) whose diagnosis and treatment were delayed resulting in serious nervous system sequelae and disability which may not be easily reversible. We discuss TBM diagnosis and use of simple clinical and laboratory features and suggest a low threshold for empirical treatment with anti-TB drug in case of suspected TBM.

Serological diagnoses for infectious diseases such as those based on disease¬specific IgM antibody detection often confuse clinicians and therefore make treatment decisions difficult. This is due to the relatively long persistence of IgM in the blood circulation following exposure to the organism or nonspecific polyclonal activation of memory cells. We report a Lao patient diagnosed as having scrub typhus on admission based on detection of IgM to Orientia tsutsugamushi and initially treated with Doxycycline. The patient became afebrile but had severe pulmonary involvement. The blood culture was subsequently positive for Leptospira spp. which is the cause of leptospirosis. The admission blood sample of the patient was negative for Orientia tsutsugamushi, Rickettsia typhi, and Rickettsia spp. DNA targets, by PCR, suggesting that the patient did not have scrub typhus, murine typhus or Spotted Fever. After one week of IV ceftriaxone treatment, the patient improved and was discharged well. The positive IgM to scrub typhus detected on admission was probably due to previous exposure to O. tsutusgamushi, and scrub typhus was not the cause of her presenting illness. Fortunately, Doxycycline, given to the patient for scrub typhus treatment, is also effective for leptospirosis preventing death. However, the patient required intravenous ceftriaxone (which would not have been effective for scrub typhus) when she developed severe disease. This patient’s illness is a reminder that clinicians should be cautious about serological diagnosis. At present, laboratory diagnosis of leptospirosis remains a big challenge for the clinicians because the existing gold standard test such as Microscopic Agglutination Test (MAT) and culture are labour intensive, expensive and seldom available. Until the development of the simple, rapid, and more reliable tests, the empirical treatment of patients with suspected leptospirosis with doxycycline, penicillins or ceftriaxone are strategies to reduce severe complications and death although it should be born in mind that penicillins and ceftriaxone will not be effective against rickettsial organisms.

Diagnosis of infective endocarditis is challenging as the clinical diversity of the disease sometimes misleads clinicians in the recognition, correct diagnosis and rapid treatment, which are important to reduce the morbidity and mortality associated with this disease. We report the case of a 14-year-old girl who presented with left axillary pain and fever. She was eventually diagnosed with infective endocarditis caused by Abiotropia defectiva, complicated by a large saccular aneurysm of the left axillary artery.