#Typhoid and Para Typhoid ((A)) Diagnosis and Comparison

Paratyphoid fever   diagnosis

Pathogen review :

salmonella enterica serotypes Typhi and Paratyphi A,

 Paratyphi B (tartrate negative), and Paratyphi C cause a potentially severe and occasionally life-threatening bacteremic illness referred to respectively as typhoid and paratyphoid fever, and collectively as ((enteric fever))

DIAGNOSIS:

First is to review in mind the Clinical presentation

The incubation period of typhoid and paratyphoid infections is 6–30 days.The onset of illness is insidious with gradually increasing fatigue and a fever that increases daily from low-grade to as high as 102°F–104°F (38°C–40°C) by the third to fourth day of illness. Headache, malaise, and anorexia are nearly universal, and abdominal pain, diarrhea, or constipation are common. Hepatosplenomegaly can often be detected. A transient, macular rash of ((rose-colored spots can occasionally be seen on the trunk.))*Fever is commonly lowest in the ((morning)), reaching a peak in late ((afternoon or evening.))this clinical presentation is often confused with: malaria, and typhoid fever should be suspected in a person with a history of travel to an endemic area who is not responding to antimalarial medication. Untreated, the disease can last for a month. The serious complications of typhoid fever generally occur after 2–3 weeks of illness and may include life-threatening intestinal hemorrhage or perforation.

Laboratory tests:

Infection with typhoid or paratyphoid fever results in a low-grade septicemia. thus blood culture is the mainstay of diagnosis in typhoid and paratyphoid fever, a single culture is positive in only approximately 50% of cases. Multiple cultures increase the sensitivity and may be required to make the diagnosis. Bone marrow culture increases the diagnostic yield to approximately 80% of cases and is relatively unaffected by prior or concurrent antibiotic use. Stool culture is not usually positive during the first week of illness, so blood culture is preferred. &  Urine culture has(( no higher diagnostic yield)) than stool culture for acute cases.

*The Widal test is unreliable but is widely used in developing countries because of its low cost. It is a serologic assay that may react in patients with typhoid or paratyphoid fever, but is not specific and false positives may occur. Serologic assays are not an adequate substitute

 for   ((blood, stool, or bone marrow culture.))

((Because there is no definitive serologic test for typhoid or paratyphoid fever, the initial diagnosis often has to be made clinically.)) The combination of a history of risk for infection and a gradual onset of fever that increases in severity over several days should raise suspicion of typhoid or paratyphoid fever. Typhoid fever is a nationally notifiable disease

Note :

the ((US National Library of MedicineNational Institutes of Health)) puplished comparism done in Egypt 1996  between paratyphoid(( A ))sever infection and typhoid fever infection which was :

Twenty eight positive blood culture paratyphoid A fever cases which may mimic the typhoid fever infection and  were studied. Forty two positive blood culture typhoid cases were taken as controls.

 Cases and controls were subjected to:

 1) careful history,(( especially young arrival from developing countries and from same country into urban areas

 2) thorough clinical examination,

 3) two blood cultures for salmonella,

 4) Widal agglutination test,

5) total and differential white blood count,

 6) urine and stool cultures following therapy.

*There was no significant difference in the clinical picture between acute paratyphoid(( A)) fever and  / acute typhoid fever except the:

 significant decrease of anorexia (57%), toxic look (54%), coated tongue (64%) in acute paratyphoid A cases when compared to acute typhoid cases.

Important note :The prevalence of extraintestinal symptoms in paratyphoid A cases may mimic viral infections. Three of the 4 classical signs namely; toxic look (54%), bronchitic chest (50%), splenomegaly (72%) and tympanitis (64%) were good bed side suggestive clinical diagnostic aids in paratyphoid A cases.

THUS: Blood culture  IS the CORNERSTONE of diagnosis of paratyphoid microbs cases. In 6 (21%), only the second blood sample was positive stressing the value of multiple cultures. Significant Widal antibody titre was elicited in only about half (57%) of paratyphoid A cases which was significantly lower than typhoid cases (83%). Leucopenia was found in only 25% of paratyphoid A cases. Eosinopenia was constant and is considered as a diagnostic and prognostic aid.

SO,

 No correlation was elicited between either the height of antibody titre or the height of leucocytic count and the severity of illness. There was no significant difference in the response to therapy or the occurrence of complications between paratyphoid(( A)) cases and typhoid cases. Up to the current knowledge, this is the first report on comparative study between acute paratyphoid A fever and acute typhoid fever in Egypt from clinical, diagnostic, therapeutic and prognostic points of view.

 Egypt Public Health Assoc.  at 1996.

Content source: 

1^st  Centers for Disease Control and Prevention
National Center for Emerging and Zoonotic Infectious Diseases (NCEZID)
Division of Global Migration and Quarantine (DGMQ)

   2^nd  Chapter 3: Infectious Diseases Related to Travel

CDC website: www.cdc.gov/typhoid-fever

Site :https://wwwnc.cdc.gov/travel/yellowbook/2018/infectious-diseases-related-to-travel/typhoid-paratyphoid-fever

3d    MEDSCPAE-Salmonella typhi and para typhiUpdated: Mar 01, 2018

Author: John L Brusch, MD, FACP; Chief Editor: Michael Stuart Bronze

4^th US National Library of MedicineNational Institutes of Health -database

Written by :saif alaa alqaisy

30-11-018