RESUMO
Nucleic acid amplification tests, including the polymerase chain reaction (PCR), are sensitive and specific tests that are often used for diagnosing sexually transmitted diseases (STDs). A pseudo-outbreak of pharyngeal gonorrhoea in a group of prostitutes turned out to have been caused by false-positive test results due to commensal oropharyngeal Neisseria species. Specific molecular tests may yield erroneous results. When the results of an STD study have major consequences at a legal or social level, it is advisable, in consultation with a medical microbiologist, to take a sample for culture or to carry out a second molecular test aimed at a different part of the bacterial genome.
Assuntos
Gonorreia/diagnóstico , Neisseria gonorrhoeae/isolamento & purificação , Doenças Faríngeas/diagnóstico , Reação em Cadeia da Polimerase/métodos , Reação em Cadeia da Polimerase/normas , Diagnóstico Diferencial , Surtos de Doenças , Reações Falso-Positivas , Feminino , Gonorreia/epidemiologia , Humanos , Técnicas de Amplificação de Ácido Nucleico , Doenças Faríngeas/epidemiologia , Sensibilidade e Especificidade , Trabalho SexualRESUMO
Two conventional PCR-enzyme immunoassays (PCR-EIAs) and two real-time PCR assays (LightCycler system; Roche Diagnostics) were evaluated as confirmation assays with cppB and 16S rRNA genes as targets. Of 765 male and female genitourinary and nasopharyngeal specimens positive for Neisseria gonorrhoeae in the COBAS AMPLICOR Chlamydia trachomatis/Neisseria gonorrhoeae PCR test (Roche Diagnostics), 229 (30%) were confirmed positive; 13 of these (5.7%) were lacking the cppB gene. Of the 534 samples (70%) that could not be confirmed, 81 (15%) showed a positive crossing point. However, melting curve analysis revealed an aberrant melting temperature in the LightCycler 16S rRNA assay; therefore, these samples were considered non-N. gonorrhoeae Neisseria species. Both of the 16S rRNA assays performed well, with positive predictive values of 99.1% and 100% for the PCR-EIAs and the real-time assays, respectively, and a negative predictive value of 99.8% for both. The cppB assays were compromised by the absence of the cppB gene in 5.7% of the N. gonorrhoeae-positive samples, resulting in negative predictive values of 96.8% and 97.6% for the PCR-EIAs and the real-time assays, respectively. Therefore, the 16S rRNA gene is preferable to the cppB gene as a target for confirmation assays. The melting curve analysis of the real-time assays provides useful additional information.
Assuntos
Chlamydia trachomatis/isolamento & purificação , Neisseria gonorrhoeae/isolamento & purificação , Reação em Cadeia da Polimerase/métodos , Sequência de Bases , Chlamydia trachomatis/classificação , Primers do DNA , Humanos , Técnicas Imunoenzimáticas , Neisseria gonorrhoeae/classificação , Reprodutibilidade dos TestesRESUMO
A 35-year-old man presented with a local swelling of the penis, which increased until the entire penis was thick and swollen. After infectious and obstructive causes had been eliminated, a diagnosis of 'penis friction oedema' was made. The swelling disappeared during several weeks of abstinence from sexual intercourse. Penile abnormalities can be divided into venereal diseases (STDs), incidental affections of the skin or mucous membranes in that location, and disorders of vascularisation and lymph drainage. A traumatic disorder of lymph drainage is sometimes referred to, unjustifiably, as 'penile venereal oedema'; it is a result of friction and manifests itself as local or total penile oedema or as a cordlike congestion of the lymphatic vessels. The diagnosis is by exclusion and the treatment is temporary abstinence from sexual intercourse.
Assuntos
Edema/diagnóstico , Doenças do Pênis/diagnóstico , Adulto , Coito , Diagnóstico Diferencial , Humanos , Masculino , Pênis/patologia , Abstinência SexualRESUMO
BACKGROUND: Acquired cerebriform intradermal naevus (CIN) is a rare form of pseudo cutis verticis gyrata. CASE REPORT: A case of acquired CIN of the scalp in a 46-year-old male patient is presented. The clinical and histopathological presentations of CIN are described and the therapeutic possibilities are discussed. CONCLUSIONS: In each individual case the physician must decide whether to do surgery or follow a wait-and-see policy. There is little risk of malignant change of CIN, and surgical excision of such lesions often involves evident mutilation.
Assuntos
Nevo Pigmentado/patologia , Couro Cabeludo/patologia , Neoplasias Cutâneas/patologia , Diagnóstico Diferencial , Humanos , Imageamento por Ressonância Magnética , Masculino , Pessoa de Meia-Idade , Invasividade Neoplásica , Nevo Pigmentado/diagnóstico , Neoplasias Cutâneas/diagnósticoRESUMO
A 27-year-old man presented with larva migrans cutanea on his left foot after a journey to the Philippines.