Differential Diagnosis for Cough, Arthalgia, Fever, and Salmon Skin
- Single Most Likely Diagnosis
- Infective Endocarditis: This condition is characterized by infection of the heart valves, which can cause fever, arthalgia, and cough. The "salmon skin" description could be indicative of Janeway lesions, a type of skin lesion associated with infective endocarditis.
- Other Likely Diagnoses
- Rheumatoid Arthritis: This autoimmune disorder can cause arthalgia, fever, and sometimes a rash. While it doesn't directly cause cough, it can be associated with interstitial lung disease, which might lead to coughing.
- Lupus: Systemic lupus erythematosus (SLE) is another autoimmune disease that can present with fever, arthalgia, and a variety of skin rashes, including those that might be described as "salmon skin." Lupus can also affect the lungs, leading to cough.
- Sarcoidosis: This condition can cause fever, arthalgia, and cough due to its effects on the lungs. Skin manifestations, including rashes, are also common in sarcoidosis.
- Do Not Miss Diagnoses
- Septic Arthritis: Although less likely, septic arthritis is a medical emergency that requires prompt treatment. It can cause fever, arthalgia, and sometimes a rash. The presence of cough might be incidental or related to another condition, but the combination of symptoms warrants consideration of septic arthritis to avoid missing this potentially deadly diagnosis.
- Meningococcemia: This severe infection can cause fever, rash (which might be described as "salmon skin" in its early stages), and can lead to arthalgia. Cough might not be a primary symptom, but the disease's rapid progression and potential for severe outcomes make it a "do not miss" diagnosis.
- Rare Diagnoses
- Whipple's Disease: A rare, systemic bacterial infection that can cause fever, arthalgia, and skin lesions, among other symptoms. While cough is not a primary symptom, the disease's rarity and the breadth of its manifestations make it a consideration in complex cases.
- Relapsing Polychondritis: This rare autoimmune disorder affects cartilage and can cause fever, arthalgia, and respiratory symptoms including cough, due to its effects on the trachea and lungs. Skin manifestations can also occur, although "salmon skin" is not typically described.