Incidence of varicella zoster virus infections of the central nervous system in the elderly: a large tertiary hospital-based series (2007-2014).

The aim of the study was to describe the clinical and epidemiological characteristics of the central nervous system (CNS) infection by varicella zoster virus (VZV) in patients older than 65 years in a tertiary community hospital. We retrospectively analysed the results of cerebrospinal fluid (CSF) testing in patients older than 65 years between 2007 and 2014 with clinically suspected VZV infection with CNS involvement. Patients whose CSF samples were positive for VZV DNA were included, as were those with negative results who simultaneously presented herpes zoster and CSF or magnetic resonance imaging findings suggestive of CNS infection, and in whom other possible aetiologies had been ruled out. The study included 280 patients. The disease was considered to be caused by a VZV infection in 32 patients (11.4%), of which 23 cases were virologically confirmed (detection of VZV DNA in CSF). The most frequent diagnosis of the patients with VZV CNS infection was encephalitis (83.3%), followed by meningitis (13.3%) and cerebellitis (3.3%). The mean annual incidence of VZV CNS infection was 3.0 cases per 100,000 inhabitants. VZV was the most common cause of encephalitis and viral meningitis, ahead of herpes simplex virus (n = 9). At the time of discharge, 12 (40%) patients showed neurological sequelae. Five patients (20%) died during hospitalization, all with encephalitis. Patients with a fatal outcome had significantly higher median age and longer delay before initiating acyclovir. In conclusion, VZV was the first cause of encephalitis in our elderly population. Despite acyclovir treatment, there was a high rate of case fatality and sequelae at discharge.

[Clinical relevance of nontuberculous mycobacteria]. / Relevancia clínica de los aislamientos de micobacterias no tuberculosas.

BACKGROUND: The isolation of nontuberculous mycobacteria (NTM) has increased in recent years largely due to the use of liquid cultivation media. In many cases such isolations lack clinical relevance, which is why the evaluation of their meaning must be carried out on the basis of international clinical criteria. This article studies the impact of using the criteria that the American Thoracic Society (ATS) has established for differentiating an infection of NTM colonisation in respiratory samples. METHODS: Microbiological and clinical study of the patients with repeated isolations of NTM in respiratory samples registered in our laboratory between 2000 and 2004. RESULTS: One hundred and sixteen positive cultivations of NTM were obtained, repeatedly isolated in 46 episodes corresponding to 42 patients. Eleven different species were identified: M. xenopi (16 cases), M. avium (12), M. kansasii (7), M. fortuitum (5), M. malmoense (2) and, finally, 1 of each of the following: M. genavense, M. simiae, M. gordonae and M. lentiflavum. It was possible to study 36 patients, of whom 17 met the criteria of the ATS, and, out of these, only 12 received specific treatment. In those cases that did not meet the ATS criteria the isolations did not have any clinical repercussion. In both the treated and untreated groups a clearly differentiated evolution was not observed. CONCLUSIONS: Facing the difficulty of attributing an etiological role to an NTM of respiratory samples, it is necessary to follow international criteria such as those of the ATS before beginning a specific treatment in order to avoid the incorrect treatment of patients.

[Evaluation of the MTD-2 test for the direct detection of Mycobacterium tuberculosis in specimens]. / Valoración de la prueba de amplificación MTD-2 para la detección directa de Mycobacterium tuberculosis en la muestra.

BACKGROUND: To evaluate the utility of the Amplified Mycobacterium Tuberculosis Direct Test (MTD-2, Gen-Probe) in the microbiological diagnosis of tuberculosis. METHODS: We evaluated the results obtained in 146 specimens with the MTD-2 test, together with those of the culture and smears. The MTD-2 test was performed on all the smear positives specimens (n=47), on the smear-negative specimens, when the test was demanded (n=19), and in other smear-negative specimens previously selected, according to the clinical history of the patient (n=80). We considered real cases of tuberculosis, those that were culture positive for Mycobacterium tuberculosis and those that were specifically treated. RESULTS: The overall sensitivity, specificity, positive and negative predictive values for the MTD test were: 95, 76, 71, and 96%, for the culture; and 84, 100, 100 and 90% and 75, 94, 89 and 86% for the smears, respectively. In smear positive specimens, the test showed a great specificity, and differentiated M. tuberculosis from other mycobacteria. In the smear negatives, the sensitivity of the test was low and so was the positive predictive value, especially in series performed with a high work load. CONCLUSIONS: Data from our study show that the MTD-2 test is a reliable method for rapid diagnosis of tuberculosis in smear positive specimens. However, due to its low sensitivity and positive predictive value, it is not recommended in the routine diagnosis of tuberculosis. Also, for this reason, whenever a positive result is obtained with a smear negative specimen, the result needs to be confirmed with another specimen.

[Bacteremia and hepatic abscess caused by Yersinia enterocolitica]. / Bacteriemia y absceso hepático causado por Yersinia enterocolitica.

Yersinia enterocolitica is a Gram-negative coccobacillus that is distributed world-wide and whose natural reservoir is found in a great variety of animals. Transmission to humans mainly occurs through the faecal-oral path although cases have been described of transmission through blood transfusions. It is isolated within a gastro-intestinal clinical picture and it rarely produces extra-intestinal disorders such as bacteraemia, abscesses, cutaneous signs, etc. The latter have been associated with different underlying diseases such as alterations of the iron metabolism, diabetes mellitus, alcoholism, malnutrition, tumours, immunosuppressant therapy and cirrhosis. We present the case of a diabetic patient who developed bacteraemia associated with hepatic abscess due to Yersinia enterocolitica.

Usefulness of antimicrobial susceptibility in the eradication of Helicobacter pylori.

The rate of eradication of Helicobacter pylori with standard triple therapy using omeprazole, amoxicillin and clarithromycin (OAC) is unacceptable in populations with high rates of clarithromycin resistance (15-20%). The aim of this study was to compare the efficacy of 10-day OAC therapy as the first-line treatment in patients diagnosed by culture with antimicrobial susceptibility or diagnosed by a (13) C-labelled urea breath test (UBT) without antimicrobial susceptibility in an area where the clarithromycin resistance rate was 15-20%. This was a retrospective cohort study of 266 patients, recruited consecutively throughout 2008. A total of 247 H. pylori-infected patients received antibiotic therapy (221 received the 10-day OAC therapy and 26 received other regimens) of which 134 patients were diagnosed by culture of gastric samples followed by antimicrobial susceptibility testing and 113 were diagnosed by UBT. In all patients, the eradication of H. pylori was checked by UBT. The cost of eradication by 10-day OAC treatment was assessed in each patient. The success rate of 10-day OAC therapy in patients diagnosed by culture and by UBT was 88% (103/117) and 49% (51/104), respectively (p <0.0005). The treatment was also more cost-effective in the former of these two groups (€571 versus €666). To perform culture and antimicrobial susceptibility of the H. pylori isolates was a more successful and cost effective strategy than empirical 10-day OAC treatment in populations with high rates of resistance to clarithromycin.