Table 1.

Summary of cases of biopsy-proven foscarnet nephropathy during CMV infection in solid organ transplantation.

Reference	Type of transplant	Indication of FOS	Time to nephropathy after FOS initiation	Peak serum creatinine	Proteinuria	Biopsy results	Outcome
[8, 9]	Kidney D+/R−	CMV syndrome Persistent high CMV viremia after 65 days of GCV	30 days (single treatment)	387 μmol/L	7 g/d	Birefringent crystal precipitation surrounded by macrophages in glomeruli and tubules. Fibrinoid thrombi. Black crystals with Von Kossa's reaction.	FOS withdrawn after 27 days. Seven months after FOS nephropathy: creatinine level at 158 μmol/L, proteinuria at 2 g/d. Second transplant biopsy: moderate interstitial fibrosis and tubular atrophy with sclerosis of half glomeruli, no crystal, and positive in situ CMV PCR.
[10]	Lung D−/R+	CMV bronchiolitis M460I mutation in the UL97 gene	35 days (second treatment; first treatment of 4 weeks)	475 μmol/L	NR	Autopsy: birefringent short crystals with angular edges in glomeruli (with rupture of capillaries and Bowman's capsule) and in tubules with tubular necrosis and granulomas.	No FOS withdrawal. Death 5.5 months after CMV disease (mild acute rejection, chronic lung rejection). Crystals found in lungs, esophagus, kidney, epicardium, pericardium, and tricuspid valve at autopsy.
[11]	Kidney D−/R+	Asymptomatic reactivation of GCV resistant strain despite prophylactic valganciclovir	21 days (single treatment)	Anuria, hemodialysis	NR	Crystals in tubules and in one-third of glomeruli with rupture of the basement membrane, tubular necrosis, and macrophages.	Multiorgan (kidney, pancreas, and myocardium) damage due to FOS crystal precipitation. Pancreatitis and myocarditis resolved. Graft loss and dialysis therapy continued.
[12]	Kidney D+/R−	CMV hepatitis and retinitis A594V mutation in the UL97 gene	After 14 days (single treatment)	157 μmol/L	NR	Birefringent crystals in the tubular lumens. Black crystals with Von Kossa's reaction.	FOS withdrawal. Ten months after FOS nephropathy: creatinine level at 112 μmol/L. Second transplant biopsy: disappearance of crystal deposition.
PR	Kidney D+/R−	CMV gastritis A594V and L595S mutations in the UL97 gene	6 days (second treatment; first treatment of 14 days)	450 μmol/L	4.5 g/g of creatininuria	Crystals in glomeruli and tubules.	FOS withdrawal followed by Brincidofovir. Second biopsy: disappearance of crystals, sclerosis of one-third glomeruli, mild interstitial fibrosis, and tubular atrophy. Third treatment with FOS: resolution of CMV disease. One year after FOS nephropathy: creatinine level at 130 μmol/L, proteinuria at 0.6 g/g.

CMV, cytomegalovirus; FOS, foscarnet; GCV, ganciclovir; NR, not reported; PCR, polymerase chain reaction; PR, present report.