Final answer:
The symptoms suggest a possible drug reaction such as drug-induced acute interstitial nephritis or a systemic reaction like Stevens-Johnson syndrome. Treatment includes stopping the drug and may involve corticosteroids and supportive care. Monitoring of kidney function and consultation with a rheumatologist for further testing are important.
Step-by-step explanation:
The clinical presentation you've described with proteinuria, blood (+/- casts), eosinophils (Eos) in the urine, fever and rash following the administration of Trimethoprim-sulfamethoxazole (Trim-sulfa) suggests a possible drug reaction or an underlying condition triggered by the drug. Given the timeframe of 1-2 weeks after taking Trim-sulfa, one possible diagnosis could be drug-induced acute interstitial nephritis (AIN) or a systemic reaction like Stevens-Johnson syndrome. Considering the administration of Trimethoprim-sulfamethoxazole, it's also crucial to rule out other conditions such as infectious diseases that the drug might have been initially prescribed to treat.
Treatment (Txt) would generally consist of immediate discontinuation of the causative drug (Trim-sulfa in this case), and depending on the severity, corticosteroids may be prescribed. Supportive care including hydration is essential, and if an autoimmune condition is suspected, as indicated by the primary care physician, referral to a rheumatologist would be necessary for further testing and management. Monitoring and management of kidney function is vital, as drug reactions can impact renal health.