A 41 year-old female was admitted to our hospital because of “fever for 8 days, rash for 7 days and knee joints pain for 5 days”.

The patient began to have fever (peak temperature 38.2℃) and slight sore-throat 8 days ago. One day later, she found some skin rashes in her extremities without itch and pain. The rashes were red and some became confluent, which looked like nettle rash. She went to the local hospital and was treated with “levofloxin and antiallergic drugs(loratadine)”. However, the symptoms had no change. Five days ago, she had knee joints pain and swelling. The pain and rash was alleviated after she was given ceftriaxone for 3 days, but she still had fever and the peak temperature rose to 39.2℃ with rigor. She was admitted to our hospital for further diagnosis and treatment. She had no cough, sputum, nausea, vomiting, night sweats and chest pain. Her sleep and appetite were normal. Her stool and urine were normal too.

There was nothing abnormal in the case history review. She had no history of drug allergy. Personal history and family history were nothing special.

Physical Examination：T38.4℃, P96/min, R19/min, BP105/65mmHg. The patient was well developed and moderately nourished. She was mentally normal and cooperative in the examination. There were some skin rashes in her extremities without tenderness. Some were confluent. There was no jaundice, no purpura on the skin, and the lymphnodes were not palpable. Her head, eyes, nose, ears, mouth were normal. Her neck was soft, and no venous engorgement. Thyroid glands were not palpable. The trachea was in midline. The chest and respiratory movements were symmetrical. There was no abnormal dullness. No abnormal breath sound. The heart rate was 96/min, regular. No pathological heart murmur. No pericardium friction sound was heard. Abdominal wall was soft without tenderness. The liver and the spleen were not palpable and there was no shifting dullness. No edema in her lower extremities, and no swelling knees.

Laboratory tests:

Blood routine test: WBC 13.0×10⁹/L, N 88.6%

Urine routine test: normal

ALT 73U/L (normal range 0-40U/L), AST 71U/L (normal range 0-40U/L)

B-Ultrosound: hepatomegaly and splenomegaly. No effusion of joints was found.

Questions:

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