Pneumonia in patients with systemic lupus erythematosus: Epidemiology, microbiology and outcomes.

Background and objective Pneumonia remains the main cause of mortality in patients with systemic lupus erythematosus (SLE). The aim of the study was to establish the clinical characteristics, microbiology and risk factors for poor prognosis in patients with SLE and pneumonia. Methods We reviewed medical records of patients with SLE (American College of Rheumatology criteria) and pneumonia who attended the emergency room in a single tertiary care center (January 2010-March 2015). We collected demographics, treatment and disease activity (SLEDAI-2K) data. Severity scales of pneumonia (CURB-65 (acronym for risk factors measured: confusion, urea nitrogen, respiratory rate, blood pressure, 65 years of age and older) and Pneumonia Severity Index (PSI)) were obtained. A negative composite outcome was defined as need for mechanical ventilation, septic shock or death secondary to pneumonia up to 30 days after discharge. We conducted a univariate and multivariable analysis. Results We studied 158 patients (76% women) with 187 episodes of pneumonia. There were no differences in age, SLE duration, SLE activity, treatment or comorbidities between patients with negative composite outcome vs the other group. In 53 episodes, patients presented with a negative composite outcome. Of these, 46 (24.6%) required intubation, 13 (7%) developed shock and 12 (6.4%) died. The most common bacteria isolated was S. aureus, and we observed a high percentage of nonhabitual microorganisms. Fifteen percent of patients who presented with a negative outcome had low values on CURB-65 and PSI scales. Conclusion Patients with SLE and pneumonia have a high risk of complications and present with a high percentage of nonhabitual microorganisms. Severity scales for pneumonia can misclassify as low risk SLE patients with poor prognosis.

The influence of hospital antimicrobial use on carbapenem-non-susceptible Enterobacterales incidence rates according to their mechanism of resistance: a time-series analysis.

BACKGROUND: Carbapenem non-susceptible Enterobacterales (CNSE) can be broadly divided into those that produce carbapenemases (carbapenemase-producing Enterobacterales (CPE)), and those that harbour other mechanisms of resistance (non-carbapenemase-producing CNSE (NCP-CNSE)). AIM: To determine the predictors of CNSE nosocomial incidence rates according to their mechanism of resistance. METHODS: A time-series analysis was conducted (July 2013 to December 2018) to evaluate the relationship in time between hospital antibiotic use and the percentage of adherence to hand hygiene with the CNSE rates. FINDINGS: In all, 20,641 non-duplicated Enterobacterales isolates were identified; 2.2% were CNSE. Of these, 48.1% and 51.9% were CPE and NCP-CNSE, respectively. Of the CPE, 78.3% possessed a blaOXA-232 gene. A transfer function model was identified for CNSE, CPE, and OXA-232 CPE that explained 20.8%, 19.3%, and 24.2% of their variation, respectively. According to the CNSE and CPE models, an increase in piperacillin-tazobactam (TZP) use of 1 defined daily dose (DDD) per 100 hospital patient-days (HPD) would lead to an increase of 0.69 and 0.49 CNSE and CPE cases per 10,000 HPD, respectively. The OXA-232 CPE model estimates that an increase of 1 DDD per 100 HPD of TZP use would lead to an increase of 0.43 OXA-232 CPE cases per 10,000 HPD. A transfer function model was not identified for NCP-CNSE, nor was there an association between the adherence to handhygiene and the CNSE rates. CONCLUSION: The use of TZP is related in time with the CPE nosocomial rates, mostly explained by its effect on OXA-232 CPE.

Consensus on the prevention, diagnosis, and treatment of Clostridium difficile infection. / Consenso sobre prevención, diagnóstico y tratamiento de la infección por Clostridium difficile.

In recent decades, Clostridium difficile infection (CDI) has become a worldwide health problem. Mexico is no exception, and therefore the Asociación Mexicana de Gastroenterología brought together a multidisciplinary group (gastroenterologists, endoscopists, internists, infectious disease specialists, and microbiologists) to carry out the "Consensus on the prevention, diagnosis, and treatment of Clostridium difficile infection", establishing useful recommendations (in relation to the adult population) for the medical community. Said recommendations are presented herein. Among them, it was recognized that CDI should be suspected in subjects with diarrhea that have a history of antibiotic and/or immunosuppressant use, but that it can also be a community-acquired infection. A 2-step diagnostic algorithm was proposed, in which a highly sensitive test, such as glutamate dehydrogenase (GDH), is first utilized, and if positive, confirmed by the detection of toxins through immunoassay or nucleic acid detection tests. Another recommendation was that CDI based on clinical evaluation be categorized as mild-moderate, severe, and complicated severe, given that such a classification enables better therapeutic decisions to be made. In mild-moderate CDI, oral vancomycin is the medication of choice, and metronidazole is recommended as an alternative treatment. In addition, fecal microbiota transplantation was recognized as an efficacious option in patients with recurrence or in the more severe cases of infection, and surgery should be reserved for patients with severe colitis (toxic megacolon), in whom all medical treatment has failed.

First case of Nocardia amamiensis pulmonary infection in Mexico.

We report a case of Nocardia amamiensis pulmonary infection in a 43-year-old immunocompromised woman. The patient was treated with imipenem/cilastatin and trimethoprim/sulfamethoxazole and had a favourable outcome. It is important that laboratories perform species identification to understand the epidemiology and susceptibility patterns of the different Nocardia spp.

Clinical consequences and transmissibility of drug-resistant tuberculosis in southern Mexico.

BACKGROUND: Consequences of drug-resistant tuberculosis (TB) in developing countries using directly observed treatment, short-course (DOTS), are not well defined. OBJECTIVE: To determine the impact of drug resistance on clinical outcome and transmission of TB under programmatic conditions. PATIENTS AND METHODS: A prospective cohort and molecular epidemiologic study was conducted in southern Mexico. Between March 1995 and February 1998 all patients with persistent cough whose sputa had acid-fast bacilli (AFB) underwent clinical and mycobacteriologic evaluation (species identification, drug susceptibility testing, and IS6110-based genotyping). Treatment was provided in accordance with Mexico's National Tuberculosis Program. Clinical and microbiologic outcomes and molecular epidemiologically defined transmission were measured. RESULTS: Mycobacterium tuberculosis was isolated from 238 of the 284 AFB smear-positive persons. The overall rate of resistance was 28.4% (new, 20.7%; retreated, 54.7%), and 10.8% (new, 3.3%; retreated, 35.8%) had multi-drug-resistant TB (ie, resistance to isoniazid and rifampin). After treatment, 75% (new, 81.0%; retreated, 52.8%) were cured, 8% (new, 7.8%; retreated, 7.5%) abandoned therapy, 9% (new, 3.9%; retreated, 28.3%) had treatment failure, and 4% (new, 3.3%; retreated, 7.5%) died. Another 2% of patients relapsed, and 9% died during a median of 24.4 months of follow-up. Drug-resistance was a strong independent risk factor for treatment failure. Being infected with multi-drug-resistant TB was the only factor associated with a decreased likelihood of being in a restriction fragment length polymorphism cluster. CONCLUSIONS: Despite the use of DOTS, patients with drug-resistant TB had a dramatically increased probability of treatment failure and death. Although multi-drug-resistant TB may have a decreased propensity to spread and cause disease, it has a profoundly negative impact on TB control.

Intravenous ciprofloxacin and ceftazidime in serious infections. A prospective, controlled clinical trial with third-party blinding.

Oral ciprofloxacin has been shown to be effective in the treatment of infections due to gram-positive cocci and gram-negative rods. The efficacy and safety of intravenous ciprofloxacin was compared with that of intravenous ceftazidime in the treatment of 59 patients with well-documented serious infections in a prospective, controlled, randomized study with a third-party blinding. Thirty-three patients were treated with intravenous ciprofloxacin (200 mg every 12 hours, plus a daily extra placebo dose); 26 patients were treated with ceftazidime (1 g every eight hours). The severity of the infections, underlying diseases, and demographic features were comparable in both groups, although there were more men in the ciprofloxacin group. For ciprofloxacin/ceftazidime treatments, respectively, the evaluated infections were: pyelonephritis (16 patients/nine patients), pneumonia (three/five), soft-tissue infections (four/zero), spontaneous peritonitis (five/two), primary bacteremia (three/eight), and other (two/two). Isolated pathogens included: Escherichia coli (22/12), Klebsiella sp. (five/four), Pseudomonas aeruginosa (two/three), Haemophilus influenzae (one/one), Proteus mirabilis (two/zero), Proteus vulgaris (one/zero), Salmonella sp. (zero/two), Plesiomonas shigelloides (one/zero), and others (one/four). The clinical responses were cure or improvement in 31 ciprofloxacin cases/21 ceftazidime cases; failure, zero/four; and indeterminate, two/one. The bacteriologic responses were eradication in 28 ciprofloxacin cases/22 ceftazidime cases; persistence, one/three; and indeterminate, four/one. Mild intolerance occurred in three ciprofloxacin cases and two ceftazidime cases. A mild increase in serum hepatic enzymes was observed in two patients in each group. Superinfections occurred in five patients: enterococcal septicemia (zero/two) and urinary tract infections (one/two). The results presented suggest that intravenous ciprofloxacin is an effective and safe antimicrobial agent for the treatment of serious infections, with an efficacy comparable with that of ceftazidime, a broad-spectrum cephalosporin. An additional advantage seems to be a lower rate of superinfections.

Bloodborne viral infections in patients attending an emergency room in Mexico City: estimate of seroconversion probability in healthcare workers after an occupational exposure.

The frequency of hepatitis C (HCV), hepatitis B (HBV), human immunodeficiency virus (HIV), and human T-cell lymphotropic virus (HTLV) I/II was determined in the emergency room of a teaching hospital. Of 909 patients, 19% had at least one infection; 7.8% had HCV, 6.9% HBV, 3.3% HIV, and 2.8% HTLV I/II. The probability that a healthcare worker would have an accident with an infected patient and seroconvert was 4.99 to 24.9 per 100,000 venipunctures for HBV, 5.6 to 8.4 for HCV, and 0.12-0.16 for HIV in our emergency room.

Cefepime versus ceftazidime for the treatment of serious bacterial infections.

The objective of this open, comparative and randomized clinical trial was to compare the safety and efficacy of cefepime and ceftazidime in the treatment of adults with severe infections. Fifty patients were included; 25 received cefepime (1 g b.i.d.) and 25 ceftazidime (1 g t.i.d.). Demographic characteristics of the groups were similar. The drugs were well tolerated and adverse reactions were minor and comparable in both groups. Forty-four patients were evaluated (22 from each group). There was a satisfactory clinical response in 86% and 77% in the cefepime and ceftazidime groups, respectively. In patients with microbiologically documented infection 83% (15/18) treated with cefepime and 64% (9/14) treated with ceftazidime responded satisfactorily (no statistical significance). In conclusion, the data confirms that cefepime is as safe and effective as ceftazidime for the treatment of serious bacterial infections, with the advantage of being administrated only twice daily.

Mycobacterium tuberculosis drug resistance in a suburban community in southern Mexico.

OBJECTIVE: To determine the impact of drug resistance (DR) on the clinical outcome and transmission of tuberculosis under programmatic conditions. METHODS: Prospective cohort and molecular epidemiologic study in the Orizaba Health Jurisdiction of Mexico. Between March 1995 and July 1999, chronic coughers with positive acid-fast bacilli (AFB) detected in sputum smear underwent clinical and mycobacteriologic evaluation (species identification, drug susceptibility testing and IS6110-based genotyping). Treatment was provided in accordance with official norms. RESULTS: Mycobacterium tuberculosis was isolated from 326/387 AFB-positive cases. The rate of DR was 24.2% and that of multidrug resistance (MDR, defined as resistance to both isoniazid and rifampin at least) was 7.7%; 78% were cured, 8% abandoned treatment, 6% failed treatment, and 5% died. An additional 13.5% received retreatment and 8.9% died during a median 28.6 months of follow up. Factors associated with DR by multivariate analysis were chronicity of tuberculosis (OR 4.8, 95%CI 2.7-8.4, P < 0.001), age >40 years (OR 1.9, 95%CI 1.1-3.2, P = 0.02) and indigenous origin (OR 0.3, 95%CI 0.13-0.75, P = 0.01). Cox-adjusted relative risks showed that MDR (RR 2.5, 95%CI 1.02-6.16, P = 0.04), HIV infection (RR 31.3, 95%CI 11.6-84.8, P < 0.001), and chronicity of tuberculosis (RR 2.1, 95%CI 1.0-4.4, P = 0.06) were associated with mortality, controlling for age. Predictors of retreatment were DR (not including MDR) (RR 2.2 95%CI 0.89-5.31, P < 0.087), MDR (RR 12.6, 95%CI 5.46-28.88, P < 0.001), and living in a household with an earthen floor (RR 2.8, 95%CI 1.27-6.13, P = 0.011). Being infected with MDR-TB was the only factor associated with a decreased likelihood of being in an RFLP cluster (OR 0.31, 95%CI 0.12-0.81, P = 0.02). CONCLUSIONS: Although MDR-TB may have a decreased propensity to spread and cause disease, it has a profoundly negative impact on tuberculosis control.

Disinfection and sterilization practices in Mexico.

We evaluated antisepsis, disinfection, and sterilization procedures at 22 hospitals in the state of Yucatan, Mexico, which provide services for approximately 80% of the population. The percentage of hospitals that followed standard recommendations for diverse antisepsis procedures were as follows: surgical scrub, 41%; surgical site preparation, 68%; central intravenous (iv) catheters, 61%; peripheral iv catheters, 86%; urinary catheters, 41%, and umbilical cord care, 5%. Inappropriate procedures typically involved the use of benzalkonium chloride and mercury compounds. Adequate sterilization procedures were observed for sharp surgical instruments in 9%, for blunt surgical instruments in 81%; for linen in 90%; for surgical brushes in 9%; for metal prostheses in 100%; for plastic prostheses in 57%; and for disinfection of endoscopes in 30%. The most common errors were the use of too short an exposure time in steam sterilizers or dry heat sterilizers, and the use of benzalkonium chloride as a sterilizing agent. Only 14% of hospitals used commercial spore preparations for autoclave monitoring. For the reuse of disposables, 50-94% of hospitals employed inappropriate sterilization or low-level disinfection procedures. Similar conditions are likely to exist in hospitals throughout the country. The establishment of strict regulations and hospital training programmes for disinfection and sterilization procedures, and the reuse of disposable devices is urgently needed in Mexico.

Comparison of ceftibuten vs. amoxicillin/clavulanic acid as antibiotic prophylaxis in cholecystectomy and/or biliary tract surgery.

A randomized, comparative, prospective clinical trial was carried out at a tertiary care center to compare the efficacy of two antibiotic regimens in the prophylaxis of postoperative infection in patients undergoing biliary tract surgery. One hundred patients undergoing cholecystectomy or biliary tract exploration were randomly allocated to one of the following antibiotic regimens: the standard regimen of three doses of amoxicillin/clavulanic acid (1000/200 mg) given by intravenous infusion, or a single dose of ceftibuten (400 mg) given orally. Patients were monitored during their stay in the hospital and over a 2 week period as outpatients. Fifty adult patients were included in each group. Mean age was 49 years, and sex distribution was 82 women and 18 men. The groups were comparable in terms of demographic characteristics and comorbidity. There were no cases of postoperative infection in the ceftibuten group, but five cases of infection occurred in the amoxicillin/clavulanic acid group (P < 0.05). No adverse effects were observed with either antibiotic. The treatment cost per patient was significantly lower for ceftibuten. The results indicate that ceftibuten is well tolerated and more effective than amoxicillin/clavulanic acid for prophylaxis following gallbladder and biliary tract surgery. In addition, ceftibuten has the advantage of being more cost-effective and easier to administer than amoxicillin/clavulanic acid so it could be considered as an alternative for antibiotic prophylaxis in these types of surgical procedures.

Mycobacterium tuberculosis infection in patients with systemic rheumatic diseases. A case-series.

OBJECTIVE: To describe the clinical characteristics of patients with systemic rheumatic diseases and tuberculosis. A retrospective case series from 1987 to 1994, drawn from a tertiary-care hospital in Mexico City, was studied. RESULTS: Thirty patients were included (20 women, 10 men), with mean age of 39.8 years (range 14-66), and a mean duration of the systemic rheumatic disease of 44 months (1-372). The rheumatic diseases included systemic lupus erythematosus (SLE) (n = 13), rheumatoid arthritis (7), polymyositis or dermatomyositis (5), and other diseases (5). During the six months previous to the diagnosis of tuberculosis, 22 patients had received corticosteroids, and 13 others immunosuppressants. Mycobacterium tuberculosis was isolated from 18 patients. Pulmonary tuberculosis was found in 10 patients, and extrapulmonary tuberculosis in 20, seven of these with miliary disease. SLE was seen in 6 of the patients with miliary tuberculosis. The clinical manifestations were: fever (67%), weight loss (67%), diaphoresis (60%), cough and sputum (53%), lymph node enlargement (43%), and dyspnea (33%). Sixteen patients had an abnormal chest film. Of 18 patients tested by PPD RT-2, 8 had an induration > 10 mm. Patients were initially treated with 3 or 4 anti-tuberculosis drugs for 15 days to 6 months, followed by 6 to 10 months of isoniazid plus rifampicin. Three relapsed, and 2 died of respiratory failure. CONCLUSIONS: This case series showed a particular pattern of tuberculosis in patients with systemic rheumatic diseases.

Tuberculosis prophylaxis in patients with steroid treatment and systemic rheumatic diseases. A case-control study.

OBJECTIVE: The aim of this study was to assess the impact of isoniazid prophylaxis in patients with systemic rheumatic diseases who attended a teaching hospital in Mexico City between 1987 and 1992. METHODS: In this case-control study, patients with systemic rheumatic diseases and tuberculosis (cases) were compared with patients with systemic rheumatic diseases without tuberculosis (controls). The groups were matched by year of hospital admission and rheumatic disease. Clinical charts were reviewed for: 1) isoniazid prophylaxis, defined as the administration of isoniazid 300 mg/day for 6 or more months in patients with exposure to steroids (prophylaxis with isoniazid was defined as complete, incomplete or any prophylaxis); 2) exposure to steroids: defined as the administration of prednisone > 15 mg/day (or its equivalent of another steroid) for 3 or more months before tuberculosis or recruitment into the study; 3) exposure to immunosuppressants, defined as the administration of any dose of azathioprine, methotrexate, cyclophosphamide, and/or 6-mercaptopurine, before tuberculosis in the cases or recruitment date in the controls; 4) reactivity to PPD; and 5) other relevant variables. RESULTS: Twenty cases and 66 controls were studied. A 70% decrease in the risk of developing tuberculosis was found among patients who received any prophylaxis with isoniazid as compared to controls: OR 0.31, 95% CI 0.09-0.98, p = 0.03. A 97% decrease was seen in those patients who received complete prophylaxis: OR 0.034, 95% CI 0.0001-0.216, p < 0.0001. The protective effect of complete prophylaxis persisted even after controlling for other potential confounders, such as age, gender, rheumatic disease, duration of rheumatic symptoms, and exposure to steroids and/or immunosuppressants. CONCLUSION: The results of this study suggest that in countries with a high prevalence of tuberculosis the use of isoniazid (300 mg/day for 6 months) in rheumatic patients with exposure to prednisone (> 15 mg/day for three or more months) may be useful to prevent tuberculosis, independently of the results of the PPD reactivity test. However, a controlled clinical trial will be required to confirm these results.

Epidemiological and biological characteristics of methicillin-resistant staphylococcal infections in a Mexican hospital.

BACKGROUND: Methicillin-resistant Staphylococcus aureus (MRSA) has spread worldwide since 1960. However, there is little information concerning methicillin-resistant coagulase-negative staphylococci (MRCNS) infections. METHODS: In order to study the clinical and epidemiological characteristics of methicillin-resistant staphylococci (MRS) infections and to determine the relationship between MRS and both synergistic hemolysis (SH) and slime production (SP), a laboratory-based survey and non-matched case-control study were carried out at a tertiary-care center in Mexico City. In regard to patients, from May 1991 to October 1992, 46 cases of MRS infection and 86 patients (controls) infected by methicillin-susceptible staphylococci (MSS) were included. Clinical and epidemiologic variables were analyzed. The isolates were identified and tested for antimicrobial susceptibility by standard methods. An MIC of oxacillin > or = 8 micrograms/mL was defined as an MRS. RESULTS: During the study, 94 nosocomial staphylococcal infections were diagnosed: S. aureus, 35 and CNS, 59; 43 (45.7%) by MRS (rate of MRS infections was 1.12 per 100 in-patients); 2 MRSA; 41 MRCNS, and only 19 were symptomatic. Three infections were community-acquired, including one MRSA and two MRCNS. After multivariate analysis, the significant risk factors were previous antimicrobial therapy (p = 0.013) and catheter-related (p = 0.009) and urinary-tract source (p = 0.0001). Forty-nine percent of MRS showed SH while only 15% of MSS (p < 0.001) showed SH, especially in 10/10 MR-S. hemolyticus. Additionally, 48% of MRCNS showed SP, as did 18% of MSCNS (p = 0.019), particularly in 15/20 MR-S. epidermidis. Of all MRS isolates, 38% showed a homogeneous phenotype, a trait associated with multi-drug resistance (p < 0.01) and SH (p < 0.001). CONCLUSIONS: CNS predominated as the cause of MRS infections in our setting. The homogenous phenotype was associated with SH and multi-drug resistance.

Piperacillin/tazobactam in the treatment of lower respiratory tract infections: an open non-comparative and multicentered trial. Latin American Clinical Research Group.

The aim of this study was to determine the clinical and bacteriological efficacy and safety of piperacillin-tazobactam (PT) (4g/500 mg IV tid) in the treatment of 107 adult patients with lower respiratory tract infections (LRTI) requiring hospitalization. Patients included were 66 men and 41 women with a mean age of 55.2 years (range 18-89), enrolled from Mexican (6) and Argentinean (5) hospitals. Ninety-nine clinically evaluable patients (92.5%), 87 with pneumonia and 12 with bronchitis, were treated for a mean period of 9.3 and 7.3 days, respectively. Response to treatment was favorable in 94.3% cases with pneumonia and 100% of cases with bronchitis; 86 cases (80.3%) were bacteriologically evaluable, 77 with pneumonia (eradication 74, persistence 1, superinfection 2), and 9 with bronchitis (eradication in all). Streptococcus pneumoniae was recovered in 24, Klebsiella pneumoniae in 21, Staphylococcus aureus in 8, Haemophilus influenzae in 7, Pseudomonas aeruginosa in 5, Enterobacter spp. in 6, Escherichia coli in 6 and other organisms in 12. Toxicity or intolerance were not observed. Our data suggest that PT is a reliable therapy for severe LRTI.

An open, multicenter clinical trial of piperacillin/tazobactam in the treatment of pediatric patients with intra-abdominal infections.

A total of 60 children with secondary peritonitis were enrolled in an open, non-comparative multicenter study designed to evaluate the safety, tolerance and efficacy of parenteral piperacillin/tazobactam (80/10 mg/kg every 8 hours) in young children. The most common diagnosis was perforated appendicitis (90%) and the three most common pathogens, obtained from the peritoneal cavity, were Escherichia coli (52 isolates), Pseudomonas aeruginosa (16 isolates) and Bacteroides sp. (19 isolates). Patients were examined daily during therapy, 4-14 days and 4-6 weeks post-therapy. Of the 60 patients, 43 were evaluable. The majority of patients had polymicrobial infections (36 patients). All the aerobic isolates were susceptible to piperacillin/tazobactam while 19 were resistant to piperacillin alone. Four of 43 clinically evaluable patients were considered a clinical failure and 3 of 40 bacteriologically evaluable patients were considered to have an unfavorable microbiological response. There were 2 clinically adverse events considered related to the study drug and several possibly related, mild and transitory, abnormalities in eosinophil counts and liver function tests. Based on the safety and efficacy results from this study, the advantages of using a single agent for the treatment of mixed infections of the peritoneal cavity and its potential activity against resistant organisms, we believe that further comparative clinical trials in children with intra-abdominal infections are warranted.

Piperacillin/tazobactam in the treatment of hospitalized patients with urinary tract infections: an open non-comparative and multicentered trial.

The aim of this multicentered, prospective and open study was to determine the clinical and bacteriological efficacy and safety of piperacillin/tazobactam (4g/500 mg IV tid) in the treatment of 79 adult patients with complicated urinary tract infections (UTI) requiring hospitalization. Forty-seven women and 32 men (mean age 54.2 years, and range 21-91) from 4 Argentinean and 6 Mexican hospitals were enrolled. Sixty-one clinically and bacteriologically evaluable patients were treated for a mean of 9.1 days (range 5-15). A favorable clinical response was seen in 83.6% and 80% at early and late assessment, respectively. Bacteriological eradication was achieved in 85.3% and 80% at early and late estimation, respectively. Escherichia coli was isolated in 33 cases, Klebsiella pneumoniae in 8, Enterococcus spp. in 7, Proteus mirabilis in 6, Pseudomonas aeruginosa in 3, Enterobacter spp. and Morganella morganii in 2. While 21% of all the clinical isolates were resistant to piperacillin, none of them was initially resistant to piperacillin/tazobactam. However, one female patient with a persistent UTI caused by E. coli developed resistance to piperacillin/tazobactam during treatment. A 64-year-old man with frontal meningioma developed purulent meningitis due to Enterobacter cloacae after neurosurgery. He was initially treated with ciprofloxacin, rifampin and amikacin and because of persistence of fever, he was moved to piperacillin/tazobactam. After 5 days of therapy, he developed coma secondary to intracranial hemorrhage and died. By then, the platelet count was normal (220,000/microliters), but the prothrombin time (19.5 seconds) and the partial thromboplastin time (63 seconds) were significantly prolonged. Our data suggest that piperacillin/tazobactam is a reliable therapy for complicated, non-complicated, community or hospital-acquired UTI.

Nocardiasis in patients with HIV infection.

The frequency of Nocardia infection in HIV-infected patients has increased during the past few years from 0.3% in 1985 to 1.8% in 1989. Although it is not of great concern as an AIDS-associated infection, the nonspecific clinical presentation in these patients might be confused with other lung infections such as tuberculosis (TB). The mortality rate can be as high as 60%. The authors diagnosed three homosexual men with nocardiasis among 1060 HIV-infected patients (0.2%) in a tertiary care center in Mexico City from 1981 to 1997. The mean age was 32 years. The CD4 count was less than 260 cells/mm3 in all these individuals. The clinical presentations were subacute sinusitis, chronic localized abdominal abscess, and acute disseminated nocardiasis. The respective associated infections were none; TB and cytomegalovirus (CMV); and candidiasis, TB, CMV, Isospora belli, and disseminated Mycobacterium avium complex (MAC). Trimethoprim/sulfamethoxazole (TMP/SMX) was the treatment in all the cases; at the time of this writing, two patients were living and one had died during the acute episode. A literature search uncovered 130 cases of Nocardia infection in HIV patients since 1982. According to the published data and our results, nocardiasis should be suspected in those HIV-infected patients who (1) do not respond to appropriate antituberculous treatment; (2) are intravenous drug users; and (3) develop a characteristic pericardial infection. Finally, adequate surgical or percutaneous drainage of abscesses are extremely valuable for diagnosis and therapy.

Antibacterial resistance of community-acquired respiratory tract pathogens recovered from patients in Latin America: results from the PROTEKT surveillance study (1999-2000).

PROTEKT (Prospective Resistant Organism Tracking and Epidemiology for the Ketolide Telithromycin) is a global surveillance study established in 1999 to monitor antibacterial resistance of respiratory tract organisms. Thirteen centers from Argentina, Brazil and Mexico participated during 1999-2000; they collected 1806 isolates (Streptococcus pneumoniae 518, Haemophilus influenzae 520, Moraxella catarrhalis 140, Staphylococcus aureus 351, S. pyogenes 277). Overall, 218 (42.1%) of the S. pneumoniae isolates had reduced susceptibility to penicillin, 79 (15.3%) were penicillin-resistant and 79 (15.3%) were erythromycin-resistant. Mexico had the highest prevalence of penicillin (76.5%) and erythromycin (31.2%) resistance. Of 77 erythromycin-resistant S. pneumoniae tested for resistance genotype, 43 possessed mef(A), 33 possessed erm(B) and 1 possessed both erm(B) and mef(A) mechanism. All S. pneumoniae isolates were fully susceptible to telithromycin, linezolid, teicoplanin and vancomycin. Among H. influenzae isolates, 88 (16.9%) produced beta-lactamase, ranging from 11% (Brazil) to 24.5% (Mexico). Among M. catarrhalis isolates, 138 (98.6%) produced beta-lactamase. Twenty-four (8.7%) of the S. pyogenes isolates were erythromycin-resistant; resistance being attributable to mefA (n=18), ermTR (n=5) and ermB (n=1). All H. influenzae, M. catarrhalis and S. pyogenes were fully susceptible to telithromycin. Methicillin resistance was found in 26.5% of the S. aureus isolates (Argentina 15%; Mexico 20%; Brazil 31.3%). Telithromycin was effective against 97.7% of methicillin-susceptible isolates. PROTEKT confirms that antibacterial resistance is an emerging problem in Latin America. The previously reported high levels of pneumococcal resistance to the beta-lactam and macrolides were exceeded. New agents that do not induce resistance or that exert low selective pressure, e.g. telithromycin, are essential to safeguard future antibacterial efficacy.

[Fulminant sepsis caused by Vibrio vulnificus. A case series]. / Sepsis fulminante por Vibrio vulnificus. Serie de casos.

BACKGROUND: Vibrio vulnificus is a marine bacteria associated with the ingestion of raw shellfish or contact with seawater. It can produce wound infection, diarrhea and sepsis. The main risk factor for infection is the presence of chronic liver disease. Prior studies have shown mortality from 40% to 63%. OBJECTIVE: Report of 8 cases of disseminated infection with V. vulnificus causing fulminant sepsis. DESIGN: Series of cases. METHODS: We reviewed the database of the laboratory of clinical microbiology from 1990 to 1999. A computer-based review of the worldwide medical literature was also accomplished. RESULTS: There were 8 cases of V. vulnificus infection. All patients had chronic liver disease, 3 also had diabetes mellitus and 1 received immunosuppressive agents. Five patients were known to have ingested raw shellfish. The mean duration of illness before death was 4 days. All patients presented with sepsis, seven had cutaneous lesions. Five patients received early antimicrobial treatment during the first 24 hours and all of them in the first 48 hours. Regardless of susceptibility to the antimicrobial agents used, the mortality was of 87.5%. Disk-diffusion test showed 100% susceptibility to imipenem, ceftazidime and tetracycline; 83% to cefepime, ticarcillin and cotrimoxazole and 50% to quinolones. CONCLUSION: The V. vulnificus infection appears in patients with chronic liver disease and it is associated with high mortality. This infection has to be suspected in high-risk patients who have eaten raw shellfish and therapy must be initiated as soon as possible.