Bacterial pathogens (non-Mycobacterium) from sputum culture and antimicrobial susceptibility.

Sputum culture of patients at Siriraj Hospital, Bangkok was 49.84% positive for bacterial pathogens in 1994 and 40.95% in 1995. The average incidence of gram-negative rods was 3.11 fold more than the combination of gram-positive cocci and gram-negative cocci. The most common gram-negative rod was Pseudomonas aeruginosa, followed by either Klebsiella pneumoniae or Acinetobacter anitratus depending on year. The most common coccus was Staphylococcus aureus. From both years, the number of Haemophilus influenzae, Streptococcus pneumoniae, Burkholderia pseudomallei and Nocardia spp isolated were 122, 93, 13 and 11 strains respectively. For antimicrobial susceptibility, P. aeruginosa was sensitive to ceftazidime, imipenem, gentamicin, amikacin, netilmicin, ciprofloxacin (range 56-89%). S. aureus (MSSA) was sensitive to common used drugs. S. aureus (MRSA) was sensitive to co-trimoxazole, fosfomycin, vancomycin (range 57-100%) and resistant to most drugs.

Antimicrobial therapy in Plesiomonas shigelloides-associated diarrhea in Thai children.

A retrospective case-controlled study was performed in 36 Thai children with Plesiomonas shigelloides (P. shigelloides)-associated diarrhea admitted to the Department of Pediatrics, Faculty of Medicine, Siriraj Hospital, Mahidol University from August 1990 to December 1992. Nineteen cases received antibiotics while seventeen did not receive any. The two groups were comparable in age, sex, duration of fever, duration and severity of diarrhea and medical treatment. The antibiotics given were norfloxacin, wintomylon, colistin, gentamicin, ceftriaxone, co-trimoxazole and ampicillin. In our study, 100% of P. shigelloides isolates were susceptible to quinolones and cephalosporins, while only 9% were susceptible to ampicillin. Co-trimoxazole, gentamicin, netilmicin, chloramphenicol and nalidixic acid showed high susceptibility. The duration of fever and diarrhea after treatment was not significantly different between treatment and control groups (p > 0.05). Therefore, we conclude that antibiotics did not change the duration of fever and diarrhea in Thai children with P. shigelloides-associated diarrhea.

Septicemia in the elderly.

The epidemiologic study regarding septicemia in the elderly was done in general medical wards and intensive care units of Department of Medicine, Siriraj Hospital. The average age of the 100 patients recruited was 70.6 + 8.2 years old with the prevalence of community-acquired septicemia and nosocomial septicemia being 52% and 48% respectively. Sex, the ratio of infection from gram-negative and gram-positive organisms and the mortality rate were not significantly different between those two groups of patients. Gram-negative septicemia constituted 70% of all infections i.e. 2-2.5 time of gram-positive septicemia. The most frequent causative organisms were E. coli (19%) and nonfermentative gram-negative rod (18-%) whereas Staphylococcus aureus was found in greatest number among gram-positive organisms (10%). The mortality rate of septicemia was 49% but only 28% could be discharged alive due to the fact that another 23% of the patients died from other causes such as from the complications of their own underlying diseases as only 2% had no any underlying disease. Cirrhosis was found to be the most serious underlying disease with the mortality rate of 1%. The most common identified site of infection was urinary tract infection (16%), however, intravascular catheter was responsible for nosocomial septicemia in the greatest extent. Serum albumin nonspecific prognostic in elderly patients with the average value of 3.01 + 0.78 gm% among the survivors and 2.55 + 0.97 gm% among the victims. Multiple logistic regression analysis showed that septic shock, hypothermia and consciousness were the independent risk factors of the mortality rate of septicemia in the elderly.

In vitro drug susceptibility of Mycobacterium other than tubercle bacilli.

MOTT were isolated from clinical specimens from the Division of Mycobacteriology, Department of Microbiology, Siriraj Hospital, Mahidol University, and also from natural sources, namely water and soil in the Bangkok area from January to December, 1987. The strains isolated were as follows: 30 M. fortuitum fortuitum, 5 M. fortuitum peregrinum 3 M. fortuitum 3 rd. biovariant complex, 3 M. chelonae chelonae, 7 M. chelonae abscessus. Of these, 5 strains were isolated from clinical specimens and the other 43 were from the environment. The pattern of drug susceptibility to antituberculous and antimicrobial agents revealed that they were resistant to antituberculous agents but susceptible to aminoglycosides (which contain a central ring of 2-deoxystreptamine) such as amikacin (83% of cultures), netilmicin (83%), gentamicin (77%) and kanamycin (75%). Some strains were sensitive to tetracyclines (35%), but all were resistant to penicillins and cephalosporins.

Comparison of culture and latex agglutination in the diagnosis of bacterial meningitis.

This preliminary study compared culture and latex agglutination in the diagnosis of bacterial meningitis. Only 23.08 per cent of meningitis patients were bacterial meningitis by culture. The causative organisms detected by culture and latex agglutination respectively were as follows: Streptococcus pneumoniae 7.69, 5.77 per cent: Haemophilus influenzae 1.92, 1.92 per cent: Neisseria meningitidis 1.92, 5.77 per cent: Salmonella species 5.77 per cent, -: Viridans streptococci 1.92 per cent, - and Nonfermentative gram-negative rod 3.85 per cent -. There was no latex reagent for the latter three organisms.