A patient was admitted to the hospital on the 7th day of the disease with complaints of high temperature, headache, pain in the muscles, especially in calf muscles. Dermal integuments and scleras are icteric. There is hemorrhagic rash on the skin. Urine is bloody. The patient was fishing two weeks ago. What is the most likely diagnosis?
Correct Answer: A
Rationale: The most likely diagnosis is A: Leptospirosis. Leptospirosis is caused by the spirochete Leptospira interrogans and is commonly transmitted through contact with water contaminated by animal urine, such as in this case of fishing. The symptoms described match those of leptospirosis, including high fever, headache, muscle pain, jaundice, hemorrhagic rash, and bloody urine. The calf muscle pain is a characteristic symptom of leptospirosis known as "Weil's disease." Yersiniosis (B) typically presents with abdominal symptoms, Salmonellosis (C) with gastrointestinal symptoms, and Brucellosis (D) with flu-like symptoms. Therefore, based on the symptoms and history provided, Leptospirosis is the most likely diagnosis.