Scrub-typhus: diagnosis and medical treatment

2021-07-21 05:12 PM

Scrub-typhus is an infectious disease, transmitted through the bite of tick larvae, acute onset, varied manifestations, fever, skin sores, rash, swollen lymph nodes, multiple organ and visceral lesions.

Scrub-typhus is a contagious disease, transmitted by the bite of tick larvae, acute onset, varied manifestations, including fever, skin sores, rash, swollen lymph nodes, multiple organ lesions, and coating organs; can be severe, leading to death, but progresses well and recovers quickly with appropriate treatment.

Cause of the disease: Orfentia tsutsugamushi. The source of the disease and its vector is Leptotrombidium mite. Typhoid fever circulates mainly in rural areas, forests, and mountains. The disease often appears sporadically, can occur all year round, peaking in the spring-summer - autumn months.

Clinical symptoms

Incubation period: 6-21 days (average 9-12 days).

Fever: often sudden; continuous high fever, may be accompanied by chills, headache, body aches.

Skin and mucosal manifestations:

Congestive skin, possibly mild swelling under the skin of the face and dorsal area; conjunctival congestion of the eye.

Skin sores: is a specific sign of typhus; oval shape, 0.5-2cm in size, with black or scaly scales; Usually painless, localized in soft skin areas such as armpits, chest, neck, groin, abdomen, etc..

Skin rash: usually appears at the end of the first week of the disease, has a maculopapular form, distributed mainly on the trunk, possibly on the limbs; purpura may occur.

Swollen lymph nodes; swollen lymph nodes at ulcer site, lymph nodes in the whole body; Size 1.5 - 2cm, soft, painless, normal mobility.

Enlarged liver, enlarged spleen: seen in some patients; In some cases there is jaundice.

Lung damage: patients often have a cough; auscultation may have rales; some patients have pleural effusion; Severe cases of fever with difficulty breathing, acute respiratory failure.

Cardiovascular damage: patients often have low blood pressure; Myocarditis may be present.

Meningitis, encephalitis are seen in rare cases.


Blood count: white blood cells normal or increased; the proportion of lymphocytes and monocytes is often increased; Platelets may below.

Chest X-ray: bronchitis-type lesions; Some patients have pneumonia lesions.

Liver function: often seen increased AST, ALT; May increase bilirubin, decreased albumin.

Renal function: urine contains protein and red blood cells. Renal failure (hyper uremia and creatinine) has been reported in rare cases and is usually reversible with appropriate treatment.

Ultrasound: may have hepatosplenomegaly, pleural effusion, the peritoneum.

Differential diagnosis

Typhoid also presents with fever, hepatosplenomegaly, and damage to many organ systems and viscera.

Unlike typhoid fever, typhoid usually has a subacute onset and is accompanied by gastrointestinal symptoms.

Erythema in typhoid is small, distributed mainly in the abdomen and chest. Signs of abdominal distension and rumbling right iliac fossa are very specific for typhoid. Blood tests often show low white blood cells; cultures of blood, feces, and some other specimens growing typhoid bacteria (s.typhi, s.paratyphi of all kinds).

Leptospira disease: acute illness, the main manifestation is fever, muscle pain, possible rash, jaundice, lung damage, kidney failure; Blood tests may also show thrombocytopenia, elevated liver enzymes. Signs suggestive of a diagnosis of leptospirosis are muscle pain and renal failure.

Arbovirus infections: often have an acute course with symptoms of fever, headache, fatigue, and possibly a rash. Arbovirus infections are not usually associated with hepatosplenomegaly, rarely have multiple organ manifestations and visceral edema, and usually resolve spontaneously within 5-7 days.

Other rickettsial infections (rat fever and rash group rickettsial fever). Symptoms similar to typhus, including fever, headache, fatigue, rash, damage to some organs and viscera, specific skin ulcers not seen in rat fever, can be seen in fever due to rickettsia group rash but rarer in typhus. These diseases often develop benignly and also respond to therapeutic agents such as doxycycline, chloramphenicol.

Sepsis: fever, damage to many organs, and viscera as in typhus. Sepsis is rarely accompanied by congestion and skin rash, effusion of membranes, blood cultures should be done to identify the bacteria causing the sepsis.

Diagnose the cause

Serological tests to diagnose typhus:

Enzyme-linked immunosorbent antibodies (ELISA).

Indirect immunofluorescence (IFA) antibodies.

Indirect immune peroxidase (IIP) antibodies.

Antibiotic treatment

Treat with one of the following antibiotics that work for rickettsia:

Doxycycline: dose of 0.1 g x 2 tablets orally divided into 2 times a day for 5 days, take g after meals to avoid vomiting. Give the patient a supplement to take if vomiting occurs within 2 hours of taking the medication.

Azithrom ycin 500mg orally 1 tablet/day x 1-3 days. Indicated for children under 8 years old and pregnant women.

Tetracycline dose 25 - 50mg/kg body weight/day, divided into 4 times for 5 days.

Chloram phenicol average dose 50mg/kg body weight orally twice a day for 5 days.

Supportive treatment

Cool down with paracetamol or another antipyretic, cool compress, when the patient has a high fever.

Give oral (ORS solution) or intravenous fluids (0.9% sodium chloride solution, Ringer lactate, glucose 5%) if the patient has a high fever and is eating poorly. Intravenous fluid should be given with caution when the patient presents with respiratory distress - fluid infusion can aggravate respiratory failure and lead to death.

Treatment of respiratory/circulatory failure: give the patient oxygen through a nasal cannula or mask, intubation, and mechanical ventilation if the respiratory failure is severe. Place a subclavian venous catheter, control central venous pressure; Fluid replacement in combination with vasopressors (eg, dopamine) in cases of hypotension.

Treatment of renal failure: fluid replacement, diuretic.


Prevent insect bites by wearing tight clothing, clothes impregnated with insect repellent chemicals such as benzyl benzoate, and applying insect repellent chemicals such as diethyltoluamide on exposed skin.

Kill rats, use insecticides, kill insects, or burn weeds.