To explore and establish a new integral system of diagnosis of Scrub typhus by clinical manifestation combined with laboratory detection.

Total of 16 clinical cases with scrub typhus infection were collected from January to October in 2015. The epidemiological history of outdoor life, the clinical manifestations including fever, eschar, rash, clinical manifestations of the clinical signs and symptoms and the clinical examinations including blood test, procalcitonin, hepatic function, kidney function, cardiac creatase and blood coagulation function were analyzed, respectively. The integral system including clinical manifestation and laboratory tests were established, respectively. The clinical manifestation were divided into three classes. The first class including fever and eschar, each index was two scores; the second class including rash and history of outdoor life, each index was one score; the third class including respiratory symptom such as cough, expectoration, gastrointestinal symptom such as hematochezia, abdominal distension and nausea; cardiovascular symptom such as palpitation, chest congestion; neurological syndrome such as sleepiness, delirium, each index was one half score. The lab test was divided into two classes. The total counts of white blood cells (WBC), eosinophil count and procalcitonin were defined as laboratory evidence one, each index was one score; the testing index of hepatic function, kidney function, cardiac creatase and blood coagulation function were defined as laboratory evidence two, each index was one-half score. The integral from the clinical manifestation and laboratory diagnosis was calculated and its correlation between the result from immunology test of scrub typhus and integral system was analyzed. The scrub typhus was diagnosed by integral system combined clinical manifestation with laboratory detection instead of immunology test.

The antibody positive rate of Orientia tsutsugamushi was 93.75% (15/16). The antibody positive rate of Orientia tsutsugamushi tested by nest-PCR was 100% (4/4). The patients whose scores from new integral system was ≥ 8.5 scores, while the antibody of Orientia tsutsugamushi was positive.

The scores system combined with clinical manifestation and laboratory diagnosis is established, which would help to detect scrub typhus in clinical trials without antibody of Orientia tsutsugamushi or nest-PCR method.