[Ureaplasma urealyticum, Ureaplasma parvum, and Mycoplasma hominis: commensals or pathogens?] / Ureaplasma urealyticum, Ureaplasma parvum et Mycoplasma hominis: commensaux ou pathogènes?

Mycoplasma hominis, Ureaplasma urealyticum, and Ureaplasma parvum are bacteria commonly found in the urogenital tract. However, their pathogenicity in sexually active or obstetrical patients remains controversial. Therefore, determining the significance of screening and treatment for these organisms is challenging, unlike Mycoplasma genitalium which now has well-defined management guidelines. We conducted a review of the literature to clarify the clinical significance of detecting these micro-organisms. It is crucial to carefully select the few cases that warrant further investigations, in order to mitigate the risks of overdiagnosis and overtreatment.

Mycoplasma hominis, Ureaplasma urealyticum et Ureaplasma parvum sont des bactéries couramment retrouvées au niveau de la sphère urogénitale. Toutefois, leur pathogénicité chez le patient sexuellement actif ou la femme enceinte reste encore controversée. Il est dès lors difficile de déterminer l'intérêt du dépistage et du traitement pour ces germes, à l'inverse de Mycoplasma genitalium dont la prise en charge est maintenant très encadrée. Nous avons effectué une revue de la littérature afin de clarifier la pertinence clinique de la recherche de ces microorganismes. Il est impératif de sélectionner précisément les situations nécessitant des investigations plus poussées, afin de modérer le risque de surdiagnostic et de surtraitement.

[Myases from here and elsewhere†: pseudo-furonculosis and Ignatzschineria larvae bacteremia]. / Myiases d'ici et d'ailleurs†: pseudo-furonculose et bactériémie à Ignatzschineria larvae.

Myiasis is an infestation by maggots. In humans, it predominates in regions with low socio-economic development. We report on two cases of myiasis acquired during a tropical travel and in Switzerland, respectively. The first one presented as a furunculous-like disease due to the invasion of subcutaneous tissues by Cordylobia sp. larvae. The second corresponded to a chronic wound infestation that resulted in a rarely reported bacteremia due to Ignatzschineria larvae, a commensal bacteria of maggots' digestive tract. Surgery was necessary in both cases, mainly for psychological reasons in the first case. Both the entomologist and molecular biology were instrumental for treatment decisions.

La myiase est une infestation par des larves de mouches. Chez l'homme, elle prédomine dans les régions à faible niveau socio-économique. Nous rapportons ici deux cas de myiase, l'un acquis lors d'un voyage sous les tropiques et l'autre autochtone : une myiase furonculaire due à la pénétration d'une larve de diptère dans la peau, en l'occurrence Cordylobia sp. ; et une myiase de plaie survenue par ponte de mouches dans des tissus nécrotiques, avec une exceptionnelle bactériémie secondaire, due à une bactérie commensale du tractus digestif de ces larves, Ignatzschineria larvae. Dans les deux situations, la chirurgie a été nécessaire, pour une indication surtout d'ordre psychologique dans la première. Dans les deux cas, l'apport de l'entomologiste et de la biologie moléculaire a été déterminant dans la décision thérapeutique.

[Common causes of infectious mononucleosis]. / Causes fréquentes de mononucléose infectieuse.

Most cases of infectious mononucleosis are caused by Epstein-Barr virus (EBV). However, other rare but potentially serious etiologies need to be considered. Cytomegalovirus (CMV) and Toxoplasma gondii infections, although generally benign, can cause severe congenital infections. An acute infection by the human immunodeficiency virus (HIV) can also mimic infectious mononucleosis. Laboratory diagnostic of those infections relies primarily on the detection of specific antibodies and antigens. The interpretation of laboratory results can be impeded by cross-reactions or persistence over several months of markers of acute infection. This article reviews the most common causes of infectious mononucleosis and their diagnosis.

La majorité des cas de mononucléose infectieuse sont dus à une infection par le virus d'Epstein-Barr (EBV). D'autres étiologies plus rares peuvent cependant avoir des conséquences graves. L'infection primaire à cytomégalovirus (CMV) ou la toxoplasmose, généralement bénignes, peuvent causer des infections congénitales sévères. Une primo-infection par le virus de l'immunodéficience humaine (VIH) peut également se présenter sous forme de mononucléose. Le diagnostic de ces infections repose sur la détection d'anticorps et d'antigènes spécifiques. Les problèmes de réactions croisées ou de persistance des marqueurs d'infection aiguë durant plusieurs mois rendent parfois délicate l'interprétation des résultats de laboratoire. Cet article passe en revue les causes les plus fréquentes de mononucléose infectieuse et leur approche diagnostique.

[Preanalytical step in bacteriology : a practical overview for family physicians]. / Etape préanalytique en bactériologie : aspects pratiques à l'attention du médecin praticien.

Physicians play a key role in the accuracy of bacteriological results by appropriate prescription and the quality of sample collection, preservation and transport. Samples for diagnostic purposes are of use if analysis results have an impact on the therapeutic approach. They have minimal risk of contamination, are usually obtained invasively, and may be targeted to detection of specific bacteria. Physicians should refer to the laboratory technical manual to provide proper sample quality. Furthermore, they have to provide clinical and administrative information to the microbiologist, because the laboratory analytical process depends on these. Close collaboration between physicians and microbiologists is essential.

Le médecin contribue considérablement à la fiabilité des résultats de bactériologie par l'adéquation de sa prescription, la qualité de son prélèvement, de son conditionnement et de son transport. Un prélèvement à visée diagnostique est utile si le résultat de l'analyse influe sur l'attitude thérapeutique. Il présente un risque de contamination minimal, est généralement obtenu de manière invasive, ou est destiné à la recherche de germes désignés. Pour la prise en charge correcte des échantillons, le médecin se référera au guide technique du laboratoire. De plus, il veillera à fournir au microbiologiste les renseignements cliniques et administratifs, puisque d'eux dépend la démarche analytique opérée au laboratoire. Une collaboration étroite entre médecins et microbiologistes est décisive.

[HIV-associated non-AIDS conditions]. / HIV und Komorbidität.

Antiretroviral therapy (ART) has improved quality of life and increased life expectancy of HIV-infected individuals. Opportunistic diseases are less common, and mortality has declined. Consequently, patterns of mortality and morbidity are changing among the HIV-positive population. The focus of care has shifted to ART-related problems and to various non-AIDS diseases. Such comorbidities, often occurring sequentially or concurrently, may be the consequences of long term ART toxicity, a state of chronic inflammation due to HIV infection, lifestyle-related risks for disease, and aging. The emergence of non-AIDS related conditions highlights the important role of primary care physicians, especially of those with extensive experience in HIV management.

CBFB-SMMHC is correlated with increased calreticulin expression and suppresses the granulocytic differentiation factor CEBPA in AML with inv(16).

The pericentric inversion of chromosome 16, inv(16)(p13q22), is associated with acute myeloid leukemia (AML) subtype M4Eo that is characterized by the presence of myelomonocytic blasts and atypical eosinophils. This rearrangement fuses the CBFB and MYH11 genes, with the latter encoding the smooth muscle myosin heavy chain (SMMHC). The myeloid transcription factor CCAAT/enhancer-binding protein alpha (CEBPA) is crucial for normal granulopoiesis. Alterations of structure and expression of CEBPA have been implicated in particular subtypes of AML. Here, we found that conditional expression of core-binding factor beta (CBFB)-SMMHC in U937 cells suppresses CEBPA protein expression and binding activity. However, CEBPA mRNA levels remained unchanged. No differences were detected in CEBPA mRNA levels in patients with inv(16) AML-M4Eo (n = 12) compared to patients with AML with a normal karyotype and M4 subtype (n = 6), whereas CEBPA protein and binding activity were significantly reduced in patients with CBFB-SMMHC. Furthermore, calreticulin, an inhibitor of CEBPA translation, was induced on mRNA and protein level in CBFB-SMMHC patients with AML and after expression of CBFB-SMMHC in the U937-cell system. Inhibition of calreticulin by siRNA restored CEBPA levels. Our results suggest that modulation of CEBPA by calreticulin represents a novel mechanism involved in the differentiation block in CBFB-SMMHC AML.