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Various diagnostic methods have been described to detect Neisseria gonorrhoeae. Collection of first void urine is advantageous because it is non-invasive, reproducible, and painless; and provides specimens that have already been used for detection of N. gonorrhoeae by molecular tools. The purpose of this study was to assess the usefulness of first void urine for detection of N. gonorrhoeae using conventional bacteriologic techniques in patients with low-grade symptoms. Investigation was focused on first void urine and urethral secretion specimens collected from 87 male patients who were undergoing diagnotic workup for suspicion of sexually transmitted infection. Direct microscopic examination of smears stained using the Gram technique and cultures on modified Thayer-Martin medium and on cooked blood agar were performed on each specimen. The prevalence of urethritis was 58.0%. Gonorrhoea was diagnosed in 7.5% of cases. The sensitivity and specificity of microscopic examination of first void urine for detection of Gram-negative diplococci were 85.7% and 97.5% respectively. First void urine was less productive than urethral secretion for detection of urethritis: sensitivity, 44.4% and specificity, 100%, and urethral flora: sensitivity, 59% and specificity of 96.9%. The good performance of first void urine specimens for detection of Gram-negative diplococci by microscopy may justify their use for identification of N. gonorrhoeae in level 1 laboratories. First void urine could also be useful for epidemiological studies and large-scale screening surveys.

Introduction: During a pneumococcal septicemia, the direct revelation of bacteria on a blood smear is rare and has been mainly described in splenectomised patients., Observation: A 62 year-old non-splenectomised man suffering from myeloma died, a few hours after his admission to emergency department, from a fulminant pneumococcemia, the diagnosis of which had been rapidly evoked on the examination of a blood smear showing numerous Gram positive diplococci., Comments: This observation highlights the potential severity of pneumococcal infections in patients suffering from altered humoral immunity and the diagnostic interest, in this case, of a systematic routine blood smear permitting rapid initiation of appropriate treatment.

The aim of the study was to assess the relation between the direct smear observations and bacteriological results carried out on equine tracheal secretions. A total of 304 cases comprising both the direct smear (Gram stain) and the bacteriological culture, over a period of 8 years, were submitted to this retrospective study. Most of the specimens (78%) were obtained using tracheal washings while the rest (22%) originated from tracheal brushings. A total of 96 specimens (32%) were negative for both direct smear and culture. The positive predictive value of direct smears appeared high (81-96%) while the negative predictive value was lower (48-79%). Sensitivity of direct smear was considered as low and varied from 24 to 46% for tracheal brushings and from 41 to 46% for tracheal washings. Specificity of direct smear was high for both types of specimens. Results of this study indicate that the use of Gram-stained smear examination, carried out on tracheal secretions, is a technique which is specific but not very sensitive for the prediction of bacteriological culture results. Moreover, the use of tracheal washing, more than tracheal brushing, seems to increase the sensitivity of the test.