Assessment of an ultra-sensitive IFNγ immunoassay prototype for latent tuberculosis diagnosis

Worldwide there are about 1.7 billion individuals with latent tuberculosis infection (LTBI) and only 5% to 15% will develop active tuberculosis (TB). It is recommended to treat only those most at risk of developing active TB to avoid problems of drug resistance. LTBI diagnosis involves reviewing the individual’s medical history, physical examination, and biological tests. Interferon gamma release assays (IGRA) can yield “undeterminate” or “uncertain” results, which makes clinical management decisions difficult. We assessed an ultra-sensitive immunoassay prototype based on single molecule array (SiMoA) technology to evaluate its overall performance, and in particular, its performance for indeterminate and uncertain positive or negative samples, as classified by the results from the current ELISA technique used for IFNγ quantification. We analyzed samples from hospitalized or consulting patients and healthcare workers from three hospitals in Paris, previously classified as negative (n = 30), positive (n = 35), uncertain negative (n = 25), uncertain positive (n = 31), or indeterminate (n = 30). We observed that with the SiMoA assay 83.3% of the indeterminate samples became interpretable and could be classified as negative, whereas 74% of uncertain positive samples were classified as positive. Most uncertain negative samples (72%) were reclassified as uncertain positive (68%) or positive (4%). The results suggest that the ultra-sensitive SiMoA IFNγ assay could represent a useful tool for the identification of true positive and negative samples among those giving indeterminate or uncertain results with the TB IGRA assay currently used.     

Strangulation de la verge par anneau métallique compliquée d’une lésion urétrale

Penile incarceration is uncommon. The diagnosis is obvious, but extraction of the constrictive ring and repair of the damage can be challenging. The authors present the case of a 61-year-old man wh presented with pain and swelling of the penis 3 weeks after applying a metal ring (double key rings) at the base of penis for the purposes of self-mutilation. The key ring was removed immediately under local anaesthesia. One week later, a urethral fistula was observed, requiring suprapubic cystostomy. It was decided to perform secondary surgical closure of the fistula and reconstruction of the skin of the base of the penis after treatment of local sepsis. Penile incarceration should be considered to be an emergency, as the more rapidly the constrictive object is removed, the lower the risk of complications secondary to penile devascularization, urinary retention and urethral damage. The authors review the literature concerning this unusual injury and its management.     

Le syndrome de la persistance des dérivés mullèriens: A propos de quatre observations

Persistent mullerian duct syndrome is a relatively rare inherited defect of sexual differentiation characterised by failure of regression of the mullerian ducts in males. In affected individuals, the uterus and tubes are present due to a defect of synthesis or action of antimullerian hormone normally produced by testicular Sertoli cells. The authors report four cases with a mean age of 20 years. All patients were phenotypically normal males, with bilateral cryptorchidism in two cases and unilateral irreducible inguinal mass in the other two cases. The mullerian ducts were removed in two cases and left in place in two cases as they were intimately adherent to the vas deferens. Long-term follow-up was decided due to the risk of malignant transformation of these remnants recently described in literature. According to the authors, the best management of these structures is excision and orchidopexy. In the case of adult infertility with testicular atrophy, gonadectomy and androgen replacement therapy are recommended.