Laboratory Diagnosis of Enteric Fever: A Review Update

Abstract

The diagnosis of typhoid fever on clinical presentations alone is difficult, as the presenting symptoms are diverse and similar to those observed with other febrile illnesses, especially during the first weeks of the infection. Therefore, laboratory-based investigations are essential for supporting the diagnosis of the disease. The "gold standard" for diagnosis of typhoid fever is the isolation of Salmonella typhi from appropriate samples including blood, bone marrow aspirates, stool, urine and rose spots. This facility is not available in many areas where the disease is endemic. Serodiagnosis depends upon the 100-year-old Widal test, and other serological diagnostic tools have limitations because of their low sensitivity and/or specificity. The development of molecular methods for diagnosis of infectious diseases, including typhoid fever has improved the sensitivity and specificity of diagnosis. One of the molecular methods, Polymerase chain reaction (PCR) is the most sensitive and rapid method to detect microbial pathogens in clinical specimens. Antigen detection has not been investigated for well over three decades and detecting an immune response specific for typhoid fever has been done only with antibody detection. There is an urgent need for the rational design and evaluation of effective and appropriate diagnostics for typhoid fever which must include the emerging threat of S. typhi. However, monitoring of antibiotic susceptibility patterns will ensure that signs of developing resistance are detected early and that the appropriate action is taken. Therefore, this present review has been designed to describe the different diagnostic procedure of typhoid fever. [Bangladesh Journal of Infectious Diseases 2016;3(2):43-51]

Diagnosis dan Tatalaksana Demam Tifoid pada Dewasa

“…Sensitivitas kultur darah sekitar 40 -60% dan dapat dipengaruhi oleh pengobatan antibiotik, pengambilan sampel, medium kultur, durasi inkubasi, dan variasi bakteremia pada pasien. 4,6,7 Pada pemeriksaan darah perifer dapat ditemukan leukopenia, leukosit normal, atau leukositosis, aneosinofilia dan limfopenia, juga anemia ringan dan trombositopenia. Laju endap darah meningkat.…”

Fiebre tifoidea, el arte del diagnóstico por laboratorio

“…El aislamiento de S. typhi de médula ósea se considera el estándar de oro para el diagnóstico y la mayoría de autores lo reporta como más sensible (85-95 %) que el hemocultivo; sin embargo se trata de un procedimiento invasivo. Muchos estudios han demostrado una alta sensibilidad del mielocultivo, incluso con una terapia antimicrobiana previa, independientemente de la duración de la enfermedad antes del muestreo [11][12][13] . La mayor sensibilidad del cultivo de médula ósea, en comparación con el hemocultivo, se debe principalmente a la concentración de organismos viables en la médula ósea (diez veces más que en sangre) y a que estos microorganismos suelen estar protegidos de la presencia de antibióticos sistémicos 14 .…”

Analytic Hierarchy Process Model for the Diagnosis of Typhoid Fever

“…There are many types using different methods of serologic assay like the rapid dipstick assays, dot enzyme immuno-assays and agglutination inhibition tests. (Sultana et al, 2016). Typhidot (Malaysian Biodiagnostic Research SDN BHD, Kuala Lumpur, Malaysia), is an Enzyme-Linked Immunosorbent Assay (ELISA)-based method, modified into an immunodot test format; TUBEX (IDL Biotech, Sollentuna, Sweden) detects antibodies using agglutination inhibition tests and Enterocheck-WB (Zephyr Biomedicals, Goa, India), a dipstick test, which IgM antibodies.…”