ABSTRACT
A one-step polymerase chain reaction (Heminested-PCR) was designed to target the 16S rRNA fragment simultaneously using a set of primers for the universal bacterial group and a Neisseria meningitidis species-specific sequence for diagnostic purposes. The diagnostic features of the Heminested-PCR were evaluated in the study of 168 cerebrospinal fluid (CSF) specimens from 84 patients with a N. meningitidis infection, meningitis caused by unrelated bacteria and other etiologies (57 patients), or suspicious cases (27 patients) with clinical symptoms of bacterial meningitis but with negative results from bacteriological procedures. About 90% of patients with bacterial meningitis, including those suspicious cases, had prior antibiotic therapy. The sensitivity, specificity, positive, and negative predictive values found in relation to culture and/or microscopy were 91.7, 100, 100, 100, and 90.5%, respectively. In patients suspected of having bacterial meningitis, the Heminested-PCR revealed 51.9% (14 patients) positive for N. meningitidis infection and 40.7% (11 patients) positive for unrelated bacterial infections. The agreement of the Heminested-PCR with culture and/or microscopy was high and ranked as almost perfect (kappa indices > 0.856), in contrast to its agreement with other techniques. These findings speak in favor of the molecular diagnosis of meningococcal meningitis in patients who are culture- and/or microscopy-negative, due to their prior antibiotic treatment.
Subject(s)
DNA, Bacterial/cerebrospinal fluid , Meningitis, Meningococcal/diagnosis , Neisseria meningitidis/genetics , Neisseria meningitidis/isolation & purification , Polymerase Chain Reaction/methods , DNA Primers , Humans , Meningitis, Meningococcal/cerebrospinal fluid , Microbiological Techniques , Predictive Value of Tests , RNA, Ribosomal, 16S/genetics , Reproducibility of Results , Sensitivity and SpecificityABSTRACT
Adult male after swimming in flood water in an urban area presented icterohaemorrhagic leptospirosis and septicemic salmonellosis. Severe clinical signs were characterized by fever, septicemia, jaundice, vomiting, haemorrhagic diarrhea and acute kidney failure. Peritoneal dialysis and treatment with penicillin and chloramphenicol were applied. Diagnosis was made on clinical, epidemiological and laboratorial basis. There was anticorpic seroconversion specific for L icterochaemorrhagiae. Hemocultures were positive for Salmonella with antigenica structure 4,5,12:i:-, a possible monophasic variant of S. typhimurium, 05 + (4,5,12:i:1,2). The patient survived. Attention is called to the cumulative risks for diseases acquired on exposure on exposure to floods, such as this double occurrence of diseases, both of animal origin. In view of clinical signs of comparable pathogenic and epidemic expression, investigation should be directed towards laboratorial tests for concurrent diseases
