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In out of area military missions soldiers are potentially exposed to bacteria that are endemic in tropical areas and can be used as biological agents. It can be difficult to culture these bacteria due to sample contamination, low number of bacteria or pretreatment with antibiotics. Commercial biochemical identification systems are not optimized for these agents which can result in misidentification. Immunological assays are often not commercially available or not specific. Real-time PCR assays are very specific and sensitive and can shorten the time required to establish a diagnosis markedly. Therefore, real-time PCRs for the identification of Bacillus anthracis, Brucella spp., Burkholderia mallei und Burkholderia pseudomallei, Francisella tularensis und Yersinia pestis have been developed. PCR results can be false negative due to inadequate clinical samples, low number of bacteria in samples, DNA degradation, inhibitory substances and inappropriate DNA preparation. Hence, it is crucial to cultivate the organisms as a prerequisite for adequate antibiotic therapy and typing of the agent. In a bioterrorist scenario samples have to be treated according to rules applied in forensic medicine and documentation has to be flawless.

Cutaneous leishmaniasis of the New World, in particular when caused by Leishmania (L.) braziliensis, harbours the risk of lymphogenic as well as hematogenic dissemination. This may result in mucocutaneous leishmaniasis causing severe destruction of orofacial structures. Dissemination may occur years after the disappearance of the skin lesions. In contrast, cutaneous leishmaniasis of the old world, is typically restricted to the site of inoculation. Therefore, a conservative diagnostic and therapeutic approach is usually sufficient. Infections acquired in the new world should be treated systemically, if infection with Leishmania (Viannia) braziliensis complex cannot be excluded. Here we report on three Austrian soldiers, who, weeks after having participated in an international jungle patrol course in Belize, presented themselves with multiple ulcers on the upper limbs. Diagnosis of cutaneous leishmaniasis was made based upon histological evaluation of biopsies taken from several ulcers revealing the presence of leishmanial bodies, and detection of amastigote leishmania in smears of material obtained from the ulcers. As species phenotyping could not be performed, infection with L. brasiliensis as well as progression into a mucocutaneous form were possible, demanding systemic therapy. Several treatment options including local cryotherapy with liquid nitrogen, paromomycin (Humatis Pulvis, Parke-Davis) 15% topically or oral fluconazole (Diflucan, Pfizer) 200 mg/d were applied, but showed no effect. Hence, a systemic therapy with intravenous pentamidine (Pentacarinat, Gerot), three times in total, 3-4 mg/kg body weight each, led to a complete regression of the lesions within four weeks.

Human brucellosis is a multiple organ disease that presents with fever and is most often transmitted via contaminated, unpasteurized goat milk and cheese. In chronic cases, focal complications (eg, spondylitis, neurobrucellosis and endocarditis) are frequently seen. Although the disease may be severely debilitating, the mortality rate is low. Fatal cases are often due to endocarditis. Because Brucella endocarditis is a rare complication (2% to 5%), therapeutic considerations are based on single-case experiences only. Therapy includes long-term antibiotic treatment using combinations of various antimicrobial drugs and surgical valve replacement when required. A case of Brucella endocarditis complicated by the infection of two valvular prostheses implanted after involvement of the mitral and aortic valve due to rheumatic fever is described. The patient was successfully treated by a medical and surgical approach. Therapeutic strategies in Brucella endocarditis are discussed in light of the current literature.

Brucellosis is a worldwide 're-emerging' zoonosis causing high economic losses and severe human disease. Consequently, rapid and reliable, sensitive and specific, easy to perform and automated detection systems for Brucella spp. are urgently needed to allow early diagnosis and adequate antibiotic therapy in time. Real-time PCR assays using hybridization probes meet all these requirements. In 2003 various assays have been developed and evaluated for use in human and animal brucellosis. Genus-specific real-time PCR assays e.g. based on the bcsp31 gene will lead to an early diagnosis but for the purpose of epidemiological surveillance a species-specific real-time PCR deriving from the conventional AMOS (AbortusMelitensisOvisSuis)-PCR is necessary. Advantages and disadvantages of the different methods for real-time detection of Brucella spp. and a newly developed PCR-ELISA system for the high throughput of clinical samples will be discussed.

Brucellosis is a common zoonotic disease transmittable to humans from infected animal reservoirs. Malta, Rock, Gibraltar, Cyprus or Mediterranean fever, Bang's disease, intermittent typhoid or typho-malarial fever, undulant fever, etc. are just various synonyms for brucellosis. Patients suffering from this disease show unspecific symptoms, e.g. fever, chills, malaise, arthralgia, headache, tiredness and weakness. Human brucellosis may be caused by four of totally six genetically and phenotypically closely related Brucella species, i.e. B. melitensis, B. abortus, B. suis and B. canis. Although many organ systems may be involved, brucellosis is rarely fatal. Therapeutic failure and relapses, chronic courses and severe complications like bone and joint involvement, neurobrucellosis and endocarditis are characteristic for the disease. A definite diagnosis requires the isolation of Brucellae from blood, bone marrow or other tissues. However, cultural examinations are time-consuming, hazardous and not sensitive. Thus, clinicians often rely on the indirect proof of infection. The detection of high or rising titers of specific antibodies in the serum allows a tentative diagnosis. A variety of serological tests has been applied, but at least two serological tests have to be combined to avoid false negative results. Usually, the serum agglutination test is used for a first screening and complement fixation or Coombs' test will confirm its results. As Brucella ELISAs are more sensitive and specific than other serological tests, they may replace them step by step. This review will summarize advantages and disadvantages of the serological techniques used in clinical laboratories for indirect verification of human brucellosis.

Brucellosis is a world-wide re-emerging zoonosis and the most frequent laboratory-acquired bacterial infection, causing severe disease in humans with unspecific clinical signs affecting numerous organs. Contact with infected animals, ingestion of contaminated animal products and handling of Brucella isolates in laboratories are risk factors. Various other febrile illnesses, e.g. malaria, tuberculosis, typhoid fever and tularemia may present with the same symptoms. Therefore, clinical diagnosis is difficult to establish but effective therapy requires an early diagnosis. Vaccines for humans are still not commercially available. Blood culturing of Brucella is time-consuming and not reliable. Thus diagnosis is usually based on indirect serological tests, i.e. serum agglutination test, complement fixation or the Coombs test. However, these 'conventional' serological tests lack sensitivity and specificity. Hence, a combination of various tests is mandatory for a definite diagnosis. Enzyme-linked immunosorbent assays can be used for screening and confirmation of brucellosis in one step. Molecular techniques like the polymerase chain reaction and restriction fragment length polymorphism are needed to differentiate species and strains within the genus Brucella. This review will summarize advantages and disadvantages of the techniques used in clinical laboratories for direct detection and identification of Brucella spp.