[Epidemiological surveillance for multidrug-resistant microorganisms in a general ICU]

OBJECTIVE

Multidrug resistant (MDR) microorganisms represent a threat for patients admitted in Intensive Care Units (ICUs). The objective of the present study is to analyse the results of epidemiological surveillance cultures for these microorganisms in one of these units.

METHODS

General ICU. Retrospective analysis, descriptive statistics. Analysis of epidemiological surveillance cultures for MDR microorganisms in 2015. Studied microorganisms: Methicillin-resistant Staphylococcus aureus (MRSA), ESBL-and/or carbapenemase-producing Klebsiella pneumoniae (CESBL-KP) and MDR Acinetobacter baumannii (MDRAB).

RESULTS

One thousand, two hundred and fifty nine patients admitted. A total of 2,234 specimens from 384 patients were analysed (690, 634, 62 and 286 were rectal, throat, nasal and skin swabs respectively). Global APACHE II was 18.3 ± 8 versus 21.7 ± 7.8 in patients colonized/infected on admission. Global mortality was 19.7% versus 22.3% in patients colonized/infected on admission. The higher sensitivities achieved with the different samples for the different microorganism detection were as follows. MRSA: 79% and 90% for nasal and nasal + throat swabs, respectively. MDRAB: 80% and 95% for throat and throat + rectal swabs, respectively. CESBL-KP: 95% and 98% for rectal and rectal + throat swabs, respectively. 94 out of the 384 patients (24.4%) were colonized/infected with MDR at admission. 134 patients (10.6% of the total patients admitted) were colonized/infected with a total of 169 MMR during the hospital stay. MRSA has the earliest colonization/infection (9.2 ± 6.4days) and ESBL-producing Enterobacteriaceae, the latest (18.7± 16.4 days).

CONCLUSIONS

24.4% of patients were colonized/infected by MDR at admission. Nasal, throat and rectal swabs were the most effective specimens for recovering MRSA, MDRAB and CESBL-KP, respectively. The combination of two specimens improves MDR detection except for CESBL-KP. Skin swabs are worthless. The most prevalent MDR at admission were ESBL-producing Enterobacteriaceae while the most frequent hospital acquired MDR was MDRAB..

Prevalence of M. tuberculosis infection and tuberculosis disease among HIV-infected people in Spain

OBJECTIVE

To study the prevalence of Mycobacterium tuberculosis infection (MTBI) and past/current tuberculosis (TB) among human immunodeficiency virus (HIV) infected persons in Spain.

DESIGN

Longitudinal study conducted between 2000 and 2003 at 10 HIV hospital-based clinics. Data were drawn from clinical records. Associations were measured using odds ratios (ORs) and their 95% confidence intervals (95%CI).

RESULTS

Of the 1242 persons who met the eligibility criteria, most were male (75%), aged <40 years (75%) and unemployed (40%). HIV infection occurred through intravenous drug use (53%), heterosexual sex (29%) and sex between men (16%). In the initial evaluation, 315 subjects had evidence of MTBI: 84 (6.8%) had a history of TB, 23 (1.8%) current TB and 208 (16.8%) latent tuberculosis infection (LTBI). MTBI was associated with male sex, age 30-49 years, contact with a TB case, homelessness, poor education, and negatively with CD4 <100 cells/mm(3). Among subjects with MTBI, past/current TB was associated with retirement/disability (OR 6, 95%CI 1.6-22.5), CD4 <200 cells/mm(3) (OR 9.7, 95%CI 3.8-24.6), viral load >55,000 copies (OR 5.3, 95%CI 1.4-20.0), and negatively, with skilled work (OR 0.4, 95%CI 0.1-1.0) or administrative/managerial/professional work (OR 0.05, 95%CI 0.01-0.4).

CONCLUSION

Social context has an impact on the effectiveness of HIV and TB control programmes even in industrialised countries with free access to health care.

Transfusion-associated sepsis caused by Candida parapsilosis

BACKGROUND AND OBJECTIVES

The contamination of blood components by bacteria is an adverse event, which, although very uncommon, has an exceptionally high mortality rate.

CASE REPORT

A patient suffering from terminal adenocarcinoma of the ovary received a red blood cell unit. During the transfusion, the patient developed fever. Cultures of both the patient's blood and the blood unit were done, and she was treated with antibiotics. Forty-eight and seventy-two hours after the transfusion, Candida parapsilosis grew in the blood cultures of the red blood cell bag and of the patient. The infection was controlled with amphotericin. The patient died from cancer progression. CONCLUSIONS We describe the first case of transfusion-associated sepsis caused by C. parapsilosis.

Comparison of solid and liquid culture media with polymerase chain reaction for detection of Mycobacterium tuberculosis in clinical samples

The aim of this study was to determine the sensitivity of different methods--two commercial polymerase chain reaction (PCR) kits (a protocol of nested PCR and a protocol of amplification of the IS6110 insertion element), the radiometric Bactec system, the Septi-Chek AFB culture system, and culture in Löwenstein-Jensen (LJ) solid medium--for the detection of Mycobacterium tuberculosis. One hundred clinical samples from 51 patients with culture-positive tuberculosis (81 specimens) and 19 controls (19 specimens) were used. Eighty-nine percent of the samples were smear negative. In the 81 specimens obtained from patients with tuberculosis, the frequency of positivity was 66.6% for nested PCR, 63% for culture in liquid media, 38.3% for IS6110 assay, and 28.4% for culture in LJ medium. In 18 samples obtained by invasive procedures in patients with tuberculosis, mycobacterial DNA was detected by nested PCR in 83.3% (including all samples positive by culture on liquid media), by culture in liquid media in 77.7% by culture on LJ medium in 27.7%, and by the IS6110 assay in 11.1%. No false-positive results were obtained from the negative control specimens with any of the techniques tested. The sensitivity of the reamplification protocol appears to be superior to that of the IS6110 assay and similar to that of the Bactec system.

The diagnostic usefulness of a DNA probe for Mycobacterium tuberculosis complex (Gen-Probe) in Bactec cultures versus other diagnostic methods

The combination of the radiometric Bactec system and the Gen-Probe for Mycobacterium tuberculosis complex (MTB) in detection and identification of mycobacteria was evaluated. Löwenstein-Jensen and Coletsos media for isolation, and Bactec-NAP test and cellular morphology and grouping for identification of MTB and mycobacteria other than tuberculosis (MOTT) were also evaluated. The study included all specimens submitted to our laboratory for mycobacteria detection over a 6-month-period. The mean recovery times of MTB were 13.7, 23.3, and 21.2 days for Bactec, Löwenstein-Jensen and Coletsos, respectively. Bactec system recovered 87.8% of MTB strains and 98% of MOTT, and the conventional media 82.9% of MTB and 19.2% of MOTT. Ziehl-Neelsen smears and Bactec-NAP were effective in differentiating MTB and MOTT strains (3.3% and 9.6% respectively of the cultures were uninterpretable). Gen-Probe (cutoff point for MTB = 5% of hybridisation) was applied to 100 positive vials of Bactec. All cultures of MTB with a growth index (GI) > 400 displayed hybridisation > 9% (average 28.9%) but for a GI < 400, 17% of cultures showed < 5% of hybridisation (average 18.6%). All cultures for MOTT had < 5% hybridisation. With the combination Bactec/Gen-Probe the average time of the final report could be reduced to 15.5 days.

[Liposome amphotericin in the treatment of deep mycoses in patients not severely immunosuppressed. An efficient alternative with low toxicity]

Amphotericin is a powerful antifungal agent of high toxicity. Encapsulation in liposomes has led to new perspectives although clinical experience is still slight. Four patients, who were neither carriers of antibodies against the human immunodeficiency virus nor neutropenic, diagnosed of meningeal cryptococcosis, pleural aspergillosis, cerebral aspergillosis and ophthalmic candidiasis, respectively and treated with liposomal amphotericin are reported. The treatment was effective and well tolerated. Clinical improvement was observed in the patient with cerebral aspergillosis but magnetic resonance demonstrated persistence of the lesions. Only slight deterioration in renal function was observed in one case and in the other two renal failure improved upon substitution of conventional amphotericin by liposomal amphotericin. The slight systemic toxicity and the absence of local intolerance allowed the administration of high doses and shortening of the therapeutic schedule.

[Tuberculous pericarditis: diagnostic value of adenosine deaminase]

Adenosine desaminase activity was measured in the pericardiac fluid of 35 patients with pericarditis of undetermined origin who were operated upon for diagnostic or therapeutic purposes. The causes of pericarditis fell into 6 categories: I, tuberculosis (8 cases); II, idiopathy (17 cases); III, neoplasia (6 cases); IV, purulent bacterial infection (2 cases); V, constriction (2 cases) and VI, radiotherapy (1 case). The highest mean adenosine desaminase value (143 U/l) was found in group I. Other values were 34 in group II, 48 in group III and 45 in groups IV to VI. There was a statistically significant difference in this respect between group I and the other groups (P less than 0.0001). If 60 U/l is taken as discriminant value for the diagnosis of tuberculous pericarditis, then the adenosine desaminase value has a 100 percent sensitivity and an 80 percent specificity. Measuring this value therefore is a very promising procedure.

[Rhodococcus equi pneumonia in a patient with acquired immunodeficiency syndrome]

A male patient of 33 years of age with AIDS developed pneumonia with abscess formation and a slow clinical course. The sputum, bronchoalveolar lavage and blood cultures yielded a Gram-positive, partially acid-alcohol resistant bacillus which was identified as Rhodococcus equi. This organism has been uncommonly implicated in pneumonia in patients with immunodeficiency, particularly with neoplasia and severe cell immunity deficiency. It has been very rarely reported in patients with AIDS. To our knowledge, this is the first reported case in Spain.