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Two weeks ago, a 27 year-old man was admitted to the hospital because of progressive fever and weight loss. He had a normal kidney function with a serum creatinine of 1.2 mg/dL but was found to have positive blood cultures (4/4) for alpha-hemolytic streptococci and therapy with ceftriaxone was begun. You are asked to evaluate this patient after two weeks of therapy because serum creatinine has risen to 3.5 mg/dL. His general condition has improved (Tmax 37.2 C) but a diffuse maculopapular rash has developed on the trunk. Repeat blood cultures are negative. The following laboratory results were obtained: Serum creatinine 3.5 mg/dL; Serum electrolytes (mEq/L): Na 137, K 5.6, Cl 95, bicarb 18; Serum complement C3 150 mg/dL (normal 100-233), CH50 150 units/mL (normal 110-190). Urinalysis showed protein 1+, glucose negative, blood 3+, many RBCs, WBCs, and WBC casts.

Which of the following is the most likely cause of the elevation in serum creatinine?
A. Ceftriaxone-associated acute tubular necrosis
B. Glomerulonephritis secondary to subacute bacterial endocarditis
C. Acute interstitial nephritis
D. Intratubular crystal deposition
E. Renal emboli

not sure but is it A

answ was given C

where they any explanations

no, i don't have explanations for these q

ok thks

i could remember this case ,and i remember the answer was c coz.the pation developed fever at the begining and after the fever was subsided the rash appread that characteristic for acute interstitial nephritis