Epidemiologic Study of Pseudomonas aeruginosa in critical patients and reservoirs.

BACKGROUND: Pseudomonas aeruginosa is a common cause of nosocomial infections, particularly in intensive care units (ICUs). The aim of this study was to characterize P. aeruginosa clinical isolates by comparing antimicrobial susceptibility patterns with the presence of plasmids and to establish the clonal relatedness by pulsed-field gel electrophoresis (PFGE) typing. METHODS: The patients included those with isolation of P. aeruginosa hospitalized for more than 48 h in the ICU from April to May 1998. Environmental and staff cultures were obtained simultaneously. Minimal inhibitory concentrations, plasmid DNA profiles, and PFGE genomic patterns of enzyme restriction chromosomal DNA were compared. RESULTS: Sixty P. aeruginosa isolates were obtained from 197 clinical specimens, 178 environmental samples, and 47 hand cultures of personnel. Antimicrobial resistance was as follows: tobramycin 100%; ticarcillin, cefotaxime, ceftriaxone, ceftazidime, and gentamicin 80%; cefepime 60%; amikacin, ticarcillin/clavulanate, imipenem, and meropenem 40%; piperacillin and norfloxacin 20%; carbenicillin 12%, and ciprofloxacin 0%. Plasmids were detected in 11 isolates (18%). PFGE typing showed that 23 isolates belonged to a common clone (pattern A), identified from five patients, two nurses, and 10 environmental samples. Ten isolates were grouped in four clusters and 27 isolates had unrelated genomic patterns. There was no relationship among DNA genomic patterns, plasmid profiles, and susceptibility patterns. CONCLUSIONS: PFGE demonstrated the existence of a common clone in a critical care area. Reinforcement of infection control measures is needed to avoid horizontal transmission and severe infections.

Primary and acquired resistance of Mycobacterium tuberculosis in Western Mexico.

Resistance of Mycobacterium tuberculosis to antimycobacterial agents is a worldwide problem. The proposite of this study was to analyze the current resistance patterns of patients with initial episodes, as well as relapses, due to M. tuberculosis in western Mexico. From January 1993 to February 1999 a total of 237 strains of M. tuberculosis (120 from initial cases and 117 from relapse cases) were analyzed. Two hundred and four (86%) strains were isolated from the lower respiratory tract, and 33 strains (14%) from extrapulmonary sites. Twenty-three percent of M. tuberculosis isolated from patients with initial episodes were resistant to both isoniazid and rifampin, and 52% of M. tuberculosis isolated from relapse cases were also resistant to both isoniazid and rifampin.

Asymptomatic bacteriuria and inflammatory response to urinary tract infection of elderly ambulatory women in nursing homes.

BACKGROUND: Bacteriuria > or = 10(5) CFU/ml is evidence of urinary tract infection in the absence of associated signs or symptoms. The presence of pyuria with asymptomatic bacteriuria established the response of elderly women against microorganisms capable of causing invasiveness or tissue injury of the urinary tract. METHODS: The association between bacteriuria and pyuria was determined in 178 elderly, ambulatory women without symptoms of urinary tract infection in seven nursing homes. Urine culture results were subsequently analyzed in conjunction with absolute leukocyte count in urine. In this cross-sectional study, asymptomatic bacteriuria in elderly women was classified with and without pyuria. RESULTS: The prevalence of asymptomatic bacteriuria was found in 44 (24.7%) elderly women. The presence of pyuria had a sensitivity of 63.6% for bacteriuria and a specificity of 91%. The positive predictive value for the presence of pyuria predicting those with bacteriuria was 70%, and the negative predictive value for the absence of pyuria predicting those without bacteriuria was 88.4%. Escherichia coli was the most common organism isolated in 81.8% of the women. CONCLUSIONS: Bacteriuria > or 10(5) CFU/ml associated with pyuria was detected in 77% of elderly women with asymptomatic urinary tract infections. Bacteriuria of < 10(5) CFU/ml with pyuria proves less sensitive as an indicator of urinary tract infection. Elderly women with pyuria but without bacteriuria should be studied for other causes of urinary tract inflammation.

[Prevalence of hepatitis B and C virus markers among medical staff at a third-level hospital]. / Prevalencia de marcadores de virus de hepatitis B y C en personal médico de un hospital de tercer nivel.

OBJECTIVE: To determine the prevalence of HBV and HCV serologic markers in serum samples of physicians working in "Hospital de Especialidades" of "Centro Medico Nacional de Occidente (HE-CMNO)". MATERIAL AND METHODS: The presence of hepatitis B surface antigen (HBsAg) and total hepatitis B core antibodies (HBcAc) were determined by hepanostika immunoassay, and anti-HCV by ELISA method (2nd. generation). RESULTS: Sixty-two physicians from medical or surgical services were included Fifty-one males (82%) and 11 females (18%). The participants mean age was 28 years (range 25-66) and their average length of practice was 8 years (range 2-44). Four physicians (6%) had a positive pattern of HBV serologic markers indicating post HBV infection. All of them were negative for HBsAg. One physician (2%) was positive for anti-HCV. The prevalence in physicians with multiple percutaneous injuries was 25%, for those in surgical services 14%, and 24% in physicians with more than 10 years of clinical practice. CONCLUSIONS: A higher prevalence of hepatitis virus infection was observed in medical doctors with more than 10 years of clinical activity working in surgical services and those suffering multiple percutaneous injuries.

Educación para la salud en derechohabientes del primer nivel de atención médica / Health education for insured patients ar the first level of medical attention

Se efectuó un estudio en la población derechohabiente mayor de 15 años que demandaba los servicios médicos en una unidad de atención a la salud del primer nivel de atención del Instituto Mexicano del Seguro Social (IMSS) en la zona metropolitana de Guadalajara, Jalisco. El propósito fue identificar el nivel de educación para la salud de usuarios de los servicios y analizar el modelo de práctica educativa institutcional recibida por el derechohabiente. Mediante este proyecto de investigación se puede señalar que 27.1 por ciento de la población derechohabiente demandante tiene un adecuado nivel de educación para la salud, que la práctica educativa recibida se basa en la acumulación de información, y que ésta ha sido otorgada por un equipo disciplinario en salud, el cual refleja limitaciones en los métodos y técnicas de educación en salud.

Cryptosporidium sp in 300 children with and without diarrhea.

Cryptosporidium sp was searched prospectively by means of the Ziehl-Nielsen acid fast staining of stools in 403 samples obtained from patients with diarrhea (n =/152) or other non-gastrointestinal diseases (n =/152) in a six month period. Cryptosporidium was present in 11/304 samples (3.6%), 9 (81%) were taken from patients with diarrhea. Oocysts were detected in 5% of stools form malnourished (II or III) children with diarrhea; 10/11 (91%) with positive-cryptosporidium stools occurred in children less than one year of age. Cryptosporidium was present with increased frequency in malnourished children with diarrhea (p < 0.05).

[Pulmonary aspergillosis]. / Aspergilosis pulmonar.

We report a 15-year-old male with bronchial asthma since five years old, unresponsive to treatment; at age 12 a diagnosis of pulmonary tuberculosis was made and treated with several drugs. He was referred to our hospital because of hemoptysis. A diagnosis of aspergillosis in the aspergilloma form was made; after, a left upper lobectomy showed the invasive form; later he presented recurrent obstructive respiratory problems, secondary to the allergic form. Serum IgE was elevated, lowering after treatment with corticoids; simultaneously he had clinical improvement. Treatment was discontinued when clinically asymptomatic and serum IgE was normal. Diagnostic route and treatment are discussed.