[Susceptibility of non-typhi Salmonella spp. at the Galdakao Hospital (1992-1998)]. / Estudio de sensibilidad de Salmonella spp. no typhi en el Hospital de Galdakao (1992 a 1998).

Non-typhi Salmonella spp. are a common cause of gastroenteritis. In patients with a greater risk of bacteremia (those with immunosuppression, cardiovascular abnormalities, prostheses, those older than 50, especially those with atherosclerosis, and neonates) the need for antibiotic treatment may be affected by the presence of resistance. We retrospectively studied the evolution of antibiotic resistance of 917 strains isolated from feces, during the period between January 1992 and May 1998. Resistances of 32.1% to ampicillin, 14.6% to amoxicillin- clavulanic acid, 14.8% to chloramphenicol, 3.5% to trimethoprim-sulfamethoxazole and 1.8% to gentamicin were found. All the strains were susceptible to cefotaxime and ciprofloxacin. There was a distinct increase in the ampicillin resistance (12.9% in 1992 to 52.5% in 1998), amoxicillin-clavulanic acid (8.3% in 1992 to 23% in 1998), chloramphenicol (8.3% in 1994 to 23% in 1998) and trimethoprim-sulfamethoxazole (0% in 1992 to 6.6% in 1998). The typhimurium serotype showed higher resistance levels than the enteritidis serotype. Ciprofloxacin and trimethoprim-sulfamethoxazole (in children), used as first-choice antibiotics in patients with intestinal infections caused by non-typhi Salmonella spp., show excellent activity in our area.

[In vitro activity of 9 antibiotics and 3 beta-lactamase inhibitors against 107 clinical isolates of Acinetobacter baumanii]. / Actividad in vitro de nueve antibióticos y tres inhibidores de betalactamasas frente a 107 aislados clínicos de Acinetobacter baumannii.

BACKGROUND: Acinetobacter sp. is an important cause of nosocomial infections and it is often resistant to many antibiotics. In our hospital it often causes infections in patients on the intensive care unit. The aim of this study was to know the susceptibility of Acinetobacter sp. strains isolated in our hospital. METHODS: The in vitro activities of nine antimicrobial agents (ticarcillin, piperacillin, ceftazidime, imipenem, meropenem, gentamicin, tobramycin, amikacin and colistin) and three beta-lactamase inhibitors (sulbactam, clavulanate and tazobactam) against 107 clinical isolates of Acinetobacter baumannii were studied. MICs were determined by a dilution agar method, except for colistin, which we used the disk-diffusion agar method. RESULTS: Of the antimicrobial agents tested imipenem and colistin were highly active against all isolates (100% susceptibility), meropenem presented good activity (96.3% susceptibility), ticarcillin presented moderated activity (84.1% susceptibility). Most of the strains were resistant to ceftazidime (4.7% susceptibility), piperacillin (3.7% susceptibility) and the aminoglycosides (amikacin 21.5% susceptibility, gentamicin 2.8% susceptibility and tobramycin 4.7% susceptibility). Sulbactam was the most active agent among the beta-lactamase inhibitors studied (CMI90 = 4 micrograms/ml). CONCLUSIONS: Recent trends indicate increasing antimicrobial resistance of Acinetobacter baumannii, posing a serious threat to hospitalized patients. An strict attention to maintain a good housekeeping and control of the environment and of the antimicrobial usage, appears the measures most likely to control the spread of Acinetobacter baumannii in hospitals.

[Comparative study of 2 culture methods by seeding, in hemoculture bottles, the dialysis fluid from patients in continuous ambulatory peritoneal dialysis]. / Estudio comparativo de dos métodos de cultivo, por siembra en frascos de hemocultivo, de líquidos de diálisis en pacientes en diálisis peritoneal continua ambulatoria.

BACKGROUND: Peritonitis remains a major complication of continuous ambulatory peritoneal dialysis (CAPD). The accurate diagnosis of peritonitis is a requirement for a successful CAPD program. A prospective study was performed to evaluate two culture methods. METHODS: 1. Culture of 10 ml of uncentrifuged peritoneal fluid and 2. Culture of the sediment of 50 ml centrifuged and resuspended in 20 ml of distilled water, into aerobe/anaerobe hemoculture bottles (Hemoline, BioMérieux). We processed 162 PF from 138 CAPD peritonitis episodes, 33 of whom were in antimicrobial drug therapy. RESULTS: The sensibility/specificity of both methods (87.0/70.8 method 1 and 81.9/79.2) were similar. Both methods were more sensitive (p = 0.001) when the patient was no in antimicrobial drug therapy (60.6/88.6 method 1 and 69.7/92.4 method 2). We isolated 132 microorganisms, 64.4% Gram positive, 25.0% Gram negative, 4.6% anaerobes and 6.1% levures. CONCLUSION: Both methods were similar and the more important factor to increase the yield of culture is to remove the antibiotic presents in centrifuged fluid.

[Seroprevalence of delta virus and hepatitis C virus in patients with chronic infection with hepatitis B virus]. / Seroprevalencia del virus delta y de la hepatitis C en pacientes con infección crónica por el virus de la hepatitis B.

OBJECTIVE: To study the prevalence of hepatitis delta and hepatitis C viruses (HDV and HCV) in patients infected with hepatitis B virus (HBV) with and without risk behaviors for the infection by these viruses and by the human immunodeficiency virus (HIV). MATERIALS AND METHODS: Clinical and serological study (January 1990-December 1992) at Medicine Service at Galdacano Hospital of 109 patients with positive hepatitis B surface antigen and without clinical or serological evidence of acute hepatitis, 60 without risk behaviors for the infection, 45 parenteral drug abusers (PDA) and 4 homosexual males. RESULTS: Chronic HDV infection was observed in 60% of PDA and more frequently among HIV-positive patients (p < 0.05). In six of these patients the serological determination of HDV-Ag was positive. Chronic HDV and HCV infection rates in patients without risk behaviors were 1.6% and 16%, respectively. Eighty-eight percent of PDA had anti-HCV; no differences were observed between HIV-positive and HIV-negative patients (p = 0.64). CONCLUSIONS: HDV was particularly associated with parenteral drug abuse, with a similar prevalence to other surveys conducted in Spain. The higher frequency of HDV and HDV-Ag among HIV-positive patients could indicate a greater susceptibility to HDV in clinical conditions associated with immunosuppression. HCV infection occurs at early stages and is common among PDA infected with HBV, with no apparent association with patient's age, years of drug abuse or HIV infection.

[Microbiological diagnosis of peritonitis in patients undergoing continuous ambulatory peritoneal dialysis. Review of 5 years at the Hospital de Galdakao]. / Diagnóstico microbiológico de peritonitis en pacientes en diálisis peritoneal continua ambulatoria. Revisión de 5 años en el Hospital de Galdakao.

BACKGROUND: With the aim of knowing the etiology of infectious peritonitis in patients undergoing continuous ambulatory peritoneal dialysis in our Hospital and the yield of our method of culture, we have made a revision of cases recorded during a five years period. METHODS: The peritoneal fluids of 105 patients with peritonitis was processed as following: 10 ml of uncentrifuged liquid was placed in hemocultures bottles, aerobe and anaerobe (Hemoline, Biomérieux) and incubated for up to 15 days at 37 degrees C. An additional 50 ml of peritoneal fluid was centrifuged and the sediment used for Gram stain and placed on enriched chocolate agar. Plates were incubated for up to two days at 37 degrees C in 5% of CO2. During the last year of the review the sediment of 50 ml resuspended in sterile distilled water was placed, too, in hemoculture bottles. In 18 cases we had only the hemoculture bottles inoculated by the nurse of the Nephrology Service (those patients came at a time when the laboratory was closed). Subcultures were identified with routine methodology. RESULTS: 96 (91.43%) of the 105 dialysis effluents processed were culture positive; 91.67% were bacterial and 8.33% fungal peritonitis. 64 (69.56%) of the bacterial isolates were Gram positive and 28 (30.43%) Gram negative. CONCLUSION: We remark the good yield of a simple culture method and the high rate of Gram negative and fungal peritonitis.

In-vitro activity of ciprofloxacin, ceftriaxone and five other antimicrobial agents against 95 strains of Brucella melitensis.

We studied the in-vitro activity of seven antibiotics against 95 strains of Brucella melitensis isolated in blood cultures of 95 patients with brucellosis. The minimum inhibitory concentration (MIC) was measured by the agar dilution method. All strains of B. melitensis were inhibited by doxycycline at 0.25 mg/l, tetracycline at 0.5 mg/l, ciprofloxacin at 0.5 mg/l, streptomycin at 1 mg/l, ceftriaxone at 1 mg/l, rifampicin at 4 mg/l and by co-trimoxazole at 0.5/9.5 mg/l. We did not find strains resistant to any of the antibiotics studied. All antibiotics, including ciprofloxacin and ceftriaxone, showed a good in-vitro activity against B. melitensis.