A 36-year-old male patient presents with symptoms of cough, cold, fever, and rusty sputum. The sputum is negative for tuberculosis, and he has a history of traveling in China and consuming crab. Based on this information, the most likely infection is Paragonimus westermani.
- Paragonimus westermani, also known as the lung fluke, is a parasitic infection commonly associated with the consumption of raw or undercooked freshwater crabs or crayfish that harbor the larvae.
- The symptoms align with those of paragonimiasis, which include respiratory issues like cough and rusty sputum due to the presence of the parasite in the lungs.
- The travel history to China is pertinent, as regions in Asia are endemic areas for Paragonimus westermani.
- The negative sputum test for tuberculosis helps differentiate the condition from a potential TB infection, directing the diagnosis towards a parasitic cause.
Thus, given the patient's symptoms, travel history, and dietary exposure, the infection is most likely caused by Paragonimus westermani.