Renal AA Amyloidosis Secondary To Disseminated Tuberculosis: A Case Report And Literature Review

AA amyloidosis (Amyloid A) is an unusual manifestation of chronic inflammation, characterized by the deposition of serum amyloid A protein fibrils. Case Description: A 31-year-old man with a history of pulmonary tuberculosis, treated 11 years earlier; and a history of substance abuse (marijuana and cocaine), with no other known comorbidities, who presented to the emergency room of our hospital with a 9-month clinical picture of progressive edema, functional class deterioration, and significant weight loss (>15 kg). So, it was suspected reactivation of tuberculosis (TB). Pulmonary and lymphatic tuberculosis was then confirmed, along with extensive left-sided fibrothorax, for which anti-tuberculosis treatment was initiated. Additionally, the patient was diagnosed with dilated cardiomyopathy with a left ventricular ejection fraction (LVEF) of 14%, considered as severely reduced. Cardiac MRI ruled out infiltrative disease, which suggested cocaine-induced cardiotoxicity. Upon hospital admission, nephrotic syndrome and severe renal function impairment were noted, requiring the initiation of hemodialysis. Due to the presence of enlarged kidneys on ultrasound, and uncertainty about the chronicity of the renal damage, a renal biopsy was performed, which revealed chronic involvement with AA amyloid deposits. Ultimately, the combination of malnutrition and chronic multi-organ involvement, including the kidneys, plus extensive pulmonary fibrosis, heart failure, and systemic deterioration, led to the patient’s in-hospital death, 2 months after admission. Conclusion: This case highlights a patient with renal AA amyloidosis secondary to disseminated tuberculosis and chronic inflammation. In this particular case, despite being in a time where anti-tuberculosis treatments are widely available, a diagnostic and therapeutic delay of 9 months occurred, which resulted in a natural evolution of the disease, complicated by cocaine-induced toxic cardiomyopathy with fatal outcome. Keywords : AA amyloidosis, Serum amyloid A, Chronic infection, Nephrotic syndrome, Tuberculosis.