EMC - Maladies Infectieuses最新文献

Seven human pathogenic Trichosporon species have been described: T. ovoides, T. inkin, T. ashaii, T. asteroides, T. cutaneum, T. mucoides and T. loubieri. These species are causative agents of superficial infections such as the white piedra and are involved in localized or disseminated deep infections. Disseminated trichosporonosis are involved particularly in neutropenic patients with underlying haematological malignancy. To date, there is no standard classification in the Geotrichum genus. Three species are described: G. candidum, G. clavatum and G. capitatum (synonymously listed as Blastomyces capitatus) which was originally known as Trichosporon capitatum. The pathogenicity of Geotrichum spp. has been documented in those localized and disseminated human deep infections that occur, most of the time, during episods of severe and prolonged neutropenia. On the basis of in vitro susceptibility data and case reports, combination therapy is recommended for Trichosporon and Geotrichum infections. Voriconazole, or high-dose fluconazole for susceptible strains, plus amphotericin B is now used for the treatment of these rare infections.

Whooping cough is a human respiratory bacterial infection, dramatic for newborns and older patients. The causal agents of the disease are Bordetella pertussis and parapertussis. These extracellular bacteria that secrete adhesins and toxins are responsible for the local and systemic cytopathogenic effects observed during the disease. Intensive vaccination of children with killed bacteria has resulted in an important decrease of mortality and morbidity. However, generalized vaccination has conducted to a change in the transmission of the disease due to the short duration of the vaccine immunity and the lack of vaccine or natural boosters. Today, the disease affects adolescents and adults who present with an atypical cough difficult to diagnose, and who contaminate non vaccinated newborns. For this reason, many countries including France have decided to add in vaccination modalities vaccine boosters for adolescents and young adults. Nevertheless, surveillance of the disease is of great importance and must continue to analyse the consequences of such boosters which are introduced to reduce the transmission of the disease to infants too young to be vaccinated.

Tapeworms or cestodes are hermaphroditic flatworm parasites that can live as parasitic adults in the human gastrointestinal tract. Some cestodes only infect in the larval stage; they include: sparganosis due to Spirometra species, coenuriasis due to Toenia multiceps, cysticercosis due to Toenia solium, echinococcosis due to Echinococcus species, cystic echinococcosis, and alveolar echinococcosis caused by E. granulosus and E. multilocularis, respectively. The two other species, E. vogeli and E. oligarthus, cause polycystic echinococcosis but are rarely associated with human infection. Epidemiological and clinical features, together with treatment and prevention are reviewed.

Distomatosis are parasitic zoonosis caused by infection with trematodes ; humans can accidentally become the definitive host of the parasite. Infection occurs by ingestion of contaminated food (plants or raw shellfish). Clinical manifestations depend on the tropism of the fluke : hepatobiliary for fasciolasis and opisthorchiasis, pulmonary for paragonimiasis, or intestinal. Infection with Fasciola hepatica is a world-wide disease ; the other distomatosis are endemic in Africa, South America and Southeast Asia. Diagnosis, suspected in front of epidemiological facts (stay in endemic area, food habits) and hypereosinophilia, is based on the identification of the parasite or its eggs, and on serology. Drugs of choice are praziquantel, bithionol, and triclabendazole whose effectiveness, good tolerance and single dose make it now the first choice treatment. Endoscopic management is useful in biliary obstruction. Suppression of risk factor is the best way for preventive approach.

Ketolides are semi-synthetic derivatives of Erythromycin A. Telithromycin is the first introduced in clinical practice. It was developed specifically for the treatment of community-acquired respiratory tract infections, since it demonstrates bacteriological efficiency against common and atypical respiratory pathogens, as well as good diffusion in respiratory tissues. It maintains efficacy against erythromycin resistant Gram-positive cocci and seems to not induce MLS_B resistance. Telithromycin is available currently, but the other agents of this therapeutic class are not marketed yet.

Tularemia is a bacterial zoonosis caused by Francisella tularensis. In France, around a few dozen cases per year are observed, and the infection is transmitted to humans by a hare in most cases. The most common form is the ulceroglandular tularemia, but severe pulmonary or septicaemia forms can occur. Treatment depends on the severity of the clinical presentation, and consists in an antibiotherapy.

Tape worms are hermaphroditic flatworm parasites, which can live in the human intestinal tract. They have specific heteroxene cycles and are clinically mild. Among these the most frequent are the Taenia saginata and the Taenia solium. Only the latter may lead to morbidity by a larval tapeworm infection: cysticercosis (dealt in a specific chapter: Larval tapeworms infection).