Case Presentation:
A 28-year old African American male presented with flu-like symptoms and hematuria of one month duration. Patient finally visited the ER when he developed generalized aching pain. Patient admitted to cocaine and marijuana use for more than 10 years. On exam he was hypertensive with physical findings that were otherwise unremarkable.
Three years prior, the patient developed hematuria and renal insufficiency (creatinine 1.6 mg/dl) associated with proteinuria and a rash. Skin biopsy showed leukocytoclastic vasculitis; renal pathology was consistent with glomerulopathy supportive of thrombotic microangiopathy. On the current visit, massive proteinuria with a creatinine of 29.9 mg/dl was present. UDS was positive for THC and cocaine. Ultrasound showed normal kidney size with marked increased echogenicity. After admission, the patient experienced hemoptysis for which chest CT scan showed bilateral alveolar infiltrates. Subsequent bronchoscopy was negative except for findings of upper airway edema. Hemodialysis was initiated along with empiric treatment with high dose prednisolone given impression of vasculitis with multisystem involvement. Pertinent laboratory workup included positive ANA and p-ANCA at 1:640. C-ANCA and atypical p-ANCA were negative. Additionally noted were positive MPO with negative PR3 and rapid HIV tests. Repeat renal biopsy showed chronic focal segmental glomerulosclerosis with features of the collapsing variant of FGS.
Discussion:
This case illustrates a disease entity with generalized systemic symptoms, predominant renal and pulmonary manifestations along with skin lesions and a positive p-ANCA. The finding of an elevated ANCA titer predicts vasculitis with 98% accuracy. All the above features can be explained by cocaine-induced vasculitis or systemic vasculitis. Systemic vasculitis, such as microscopic polyangiitis, is unlikely due to the rapid progression of renal insufficiency and the pathology manifest on renal and skin biopsies. In the context of continued cocaine use, the above features favor cocaine-associated vasculitis. The pathophysiologic basis for cocaine-related renal injury involves renal hemodynamic changes, glomerular matrix synthesis and degradation, oxidative stress and the induction of renal atherogenesis. Cocaine-associated vasculitis can cause glomerulonephritis, but it is not clear whether it can progress to the collapsing variant of FSGS. It is plausible, however, that unabated cocaine use could lead to a rapid progression of chronic kidney disease.
Conclusions:
Cocaine-associated vasculitis is an increasingly reported phenomenon. The extent of its clinical phenotype has yet to be fully characterized. Our case demonstrates one variant of vasculitis reported in association with cocaine products which mimics other primary rheumatic diseases. Cocaine use and related clinical entities remain to be the subject of several government-issued public health advisories.