A Dutch nationwide evaluation of serological assays for detection of Borrelia antibodies in clinically well-defined patients.

Numerous tests for the detection of antibodies against Borrelia burgdorferi are commercially available. Manufacturer-derived data invariably report a high sensitivity and specificity, but comparative studies demonstrate large differences in clinical practice, especially with regard to specificity. We retrospectively collected data from validation studies for B. burgdorferi antibody assays from 8 laboratories in the Netherlands. The total number of samples was 809. Samples were selected based on clinical and laboratory parameters. We included samples from patients with erythema migrans, acrodermatitis chronicum atrophicans, and neuroborreliosis; cross-reactivity controls; and healthy controls. Data are presented from 10 enzyme-linked immunosorbent assays and 5 immunoblots. For manifestations of B. burgdorferi infection with short disease duration, the positivity rate of the assays varied significantly. In patients with long disease duration, the positivity rate differed only marginally. In cross-reactivity controls, there was significant variation in the reactivity rate. The majority of false-positive reactions are of the IgM isotype.

A Q fever outbreak in a psychiatric care institution in The Netherlands.

In May 2008 the Nijmegen Municipal Health Service (MHS) was informed about an outbreak of atypical pneumonia in three in-patients of a long-term psychiatric institution. The patients had been hospitalized and had laboratory confirmation of acute Q fever infection. The MHS started active case finding among in-patients, employees of and visitors to the institution. In a small meadow on the institution premises a flock of sheep was present. One of the lambs in the flock had been abandoned by its mother and cuddled by the in-patients. Samples were taken of the flock. Forty-five clinical cases were identified in employees, in-patients and visitors; 28 were laboratory confirmed as Q fever. Laboratory screening of pregnant women and persons with valvular heart disease resulted in one confirmed Q fever case in a pregnant woman. Of 27 samples from animals, seven were positive and 15 suspect for Coxiella burnetii infection. This outbreak of Q fever in a unique psychiatric setting pointed to a small flock of sheep with newborn lambs as the most likely source of exposure. Care institutions that have vulnerable residents and keep flocks of sheep should be careful to take adequate hygienic measures during delivery of lambs and handling of birth products.

Therapeutic drug monitoring of the HIV protease inhibitor atazanavir in clinical practice.

BACKGROUND: Therapeutic drug monitoring (TDM) is being applied for a number of antiretroviral agents. Little is known about the use of TDM for atazanavir. METHODS: This is a retrospective cohort analysis on the use of TDM of atazanavir at three clinical sites in The Netherlands. Patients were divided into three groups: (i) all patients with evaluable data of plasma atazanavir concentrations and its relationship with hyperbilirubinaemia; (ii) patients who started atazanavir without documented evidence of protease inhibitor (PI) mutations; (iii) patients who started atazanavir with documented evidence of PI mutations. The genotypic inhibitory quotient (GIQ) was calculated by dividing the mean atazanavir plasma trough concentration by the number of PI mutations. RESULTS: A total of 108 patients were included; 70 (65.8%) were using atazanavir/ritonavir (300/100 mg once daily). No significant relationship was observed between atazanavir plasma trough concentration and antiviral response in patients starting atazanavir without PI mutations (group 2; n = 82). In contrast, a significant relationship was observed between atazanavir GIQ and treatment response in patients starting atazanavir while having PI mutations (group 3; n = 26). The cut-off value for GIQ most predictive of virological failure was 0.23 mg/L/mutation: patients (n = 8) with a GIQ equal to or below this value had 50% virological failure whereas patients (n = 18) with a GIQ above 0.23 mg/L/mutation had only 11% virological failure (chi(2): P = 0.030). Atazanavir plasma trough concentrations were significantly related with the occurrence of increased total bilirubin concentrations. CONCLUSIONS: TDM of atazanavir might be beneficial for patients with documented PI resistance or patients with hyperbilirubinaemia.

Was isolation of Veillonella from spinal osteomyelitis possible due to poor tissue perfusion?

From a needle biopsy of the body of the 12th thoracic vertebra in a 74-year-old man with spinal osteomyelitis a Veillonella parvula was isolated. The significance of this bacterium as lactic acid indicator has been considered and discussed. Since this strictly anaerobic bacterium mainly uses lactic acid for energy generation, lactic acid must continuously and sufficiently have been produced in or near to the vertebrate body to permit outgrowth of this bacterium. Since neither microbial infections nor tumours could be demonstrated, we finally hypothesised that in this patient poor tissue perfusion has been the primary cause of lactic acid production.