The report, “Incidentally Diagnosed Alport Syndrome in a Patient with Drug-Induced Vasculitis,” appeared in the journal Case Reports in Neurology.
Clinicians at Baylor College of Medicine reported the case of the woman, who had stage 3 chronic kidney disease and went to the hospital after experiencing generalized malaise and vomiting for two weeks.
Her medical history included hypertension, heart failure, and paroxysmal atrial fibrillation — a type of abnormal heart rhythm — while her 38-year-old brother had end-stage kidney disease. Seven months earlier, she had started treatment with carvedilol, hydralazine, isosorbide mononitrate, and furosemide to treat her cardiac disease.
At the hospital, her serum creatinine level, a marker of kidney function, was higher than normal at 16.6 mg/dl. She also had active urine sediment, which includes blood cells. The laboratory findings indicated rapidly progressive glomerulonephritis — damage to the small kidney units that filter blood, called glomeruli. Hydralazine was then discontinued, as the clinicians suspected it could be the cause.
The patient was started on pulse dose corticosteroids, and subsequently received two hemodialysis treatments and one therapeutic plasma exchange (PLEX).
On the fourth day of hospitalization, a kidney biopsy revealed minimal inflammation. The levels of antinuclear antibodies and those targeting double-stranded DNA were high, which, together with the deteriorating renal function and the use of hydralazine, caused the clinicians to suspect DIAV.
However, ultrastructural analysis showed the characteristic features of Alport. The degree of interstitial fibrosis (scarring) and tubular atrophy, or shrinkage, was 60%, and in line with a diagnosis of Alport, alpha 3 and 5 chains of the protein type 4 collagen were not detected.
As a result of this significant fibrosis and lack of active inflammation, both corticosteroids and PLEX were discontinued. The patient’s renal function was not restored, and she opted to pursue peritoneal dialysis.
Overall, “[Alport] provided an explanation for our patient’s chronic renal impairment,” the scientists wrote.
“Clinicians must consider hereditary kidney disorders in patients with unexplained kidney disease and a positive family history,” they advised, adding that the patient’s late diagnosis precluded early treatment.