ZIKV is potentially sexually transmitted and persists in male genital secretions for a prolonged period after symptom onset. PROSPERO systematic review registration number CRD42016041475.

Objective: To analyse cases of blood culture negative endocarditis (BCNE) seen at St Thomas ' Hospital, London, between 1975 and. Methods: Data on all episodes of endocarditis with negative blood cultures seen at St Thomas' Hospital between 1975 and 2000 were collected prospectively and analysed retrospectively. Results: Sixty three patients with BCNE were seen during the study period: 48 (76%) with native and 15 (24%) prosthetic valve infection. BCNE accounted for 12.2% of the 516 cases of endocarditis seen at St Thomas' Hospital. The diagnosis of endocarditis was clinically definite by the Duke criteria in only 21% (7 of 34) of cases of pathologically proven native valve endocarditis but in 62% (21 of 34) of cases by the St Thomas' modifications of the criteria. Comparable figures for the 11 cases of pathologically proven prosthetic valve endocarditis were 45% and 73%. Despite negative blood cultures a causative organism was identified in 31 (49%) of the 63 cases: in 15 by serology (8 Coxiella burnetii, 6 Bartonella species, and 1 Chlamydia psittaci); in 9 cases by culture of the excised valve; in 3 by microscopy of the excised valve, on which large numbers of Gram positive cocci were seen although the culture was sterile; and in the other 4 by isolation from a site other than the excised valve (2 respiratory specimens, 1 from the pacemaker tip, and 1 from an excised embolus). In addition 5 of the 6 cases of Bartonella infection were confirmed by polymerase chain reaction study of the excised valve. Two thirds of the 32 patients for whom no pathogen was identified had received antibiotics before blood was cultured. Thus truly "negative" endocarditis was very uncommon (6% of the cases). Conclusion: If blood cultures are negative in definite or suspected endocarditis, serum should be analysed for Bartonella, Coxiella, and Chlamydia species antibodies, and the excised valve or (rarely) embolus should be analysed by microscopy, culture, histology, and relevant polymerase chain reaction. Other specimens may be relevant. The Duke criteria performed poorly in BCNE; St Thomas' additional minor criteria gave more definite diagnoses.

We appreciate the thoughtful comments of Drs Almonedro-Delia, Galvez-Acebal, and Rodriguez-Bano regarding our recent publication, "Association Between Surgical Indications, Operative Risk, and Clinical Outcome in Infective Endocarditis: a Prospective Study From the International Collaboration on Endocarditis." 1 These authors raise important issues for evaluating the impact of surgery on patient outcomes, particularly survival. We strongly agree that treatment selection bias and survivor bias are major issues when evaluating the impact of surgery on mortality and that the use of appropriate statistical methodologies is necessary to quantify an unbiased and causal association of the effect of surgical treatment on outcome. In our previous studies on the impact of surgery on mortality, we have used such methods, including propensity scores, 2 to account for selection bias and Cox proportional hazards models with surgery entered as a time-dependent covariate 3,4 for survivor bias adjustment. However, the objective of the current study was to evaluate the differences in clinical characteristics comparing patients treated with and without cardiac surgery for infective endocarditis, and to evaluate the relationship between surgical indications, operative risk (by using the Society of Thoracic Surgeons operative risk score), and outcome. Our results emphasize the relevance of specific surgical indications in treatment decisions in infective endocarditis, and the relationship between the Society of Thoracic Surgeons operative risk score and outcome, as well. The purpose of our study was not to determine the prognostic influence of surgery in comparison with medical therapy alone in infective endocarditis.

Sporotrichosis is a fungal infection of man and animals caused by Sporothrix complex. It usually presents as a lymphocutaneous form, but disseminated disease may occur. Given the paucity of data about HIV/AIDS and sporotrichosis co-infection, a systematic review of reported cases of HIV-associated sporotrichosis found via Pubmed (1984-2013) was done. A total of 39 papers were included, and 58 patients' data analyzed. Thirty-three (56.9 %) cases were from Brazil and 18 (31 %) from the USA. Patients' mean age was 37.8 ± 10.4 years; males predominated (84.5 %). The median CD4(+) cell count was 97 cells/mm(3). The most common clinical forms were disseminated and disseminated cutaneous with 33 (56.9 %) and 10 (17.5 %) patients, respectively. There was a correlation between CD4(+) count and clinical categories (p = 0.002). Mortality was 30 % and there was a correlation between central nervous system involvement and death (p < 0.001).