Kidney Week

Abstract: FR-PO131

Importance of Kidney Biopsy in Interstitial Nephritis Caused by Mycobacterium Tuberculosis: A Case with Negative Noninvasive Test Results

Session Information

• AKI: Diagnosis and Outcomes
  October 25, 2024 | Location: Exhibit Hall, Convention Center
  Abstract Time: 10:00 AM - 12:00 PM

Category: Acute Kidney Injury

• 102 AKI: Clinical, Outcomes, and Trials

Authors

• Martinez, Itzel Anahi, Operadora de Hospitales Angeles SA de CV, Ciudad de Mexico, Ciudad de México, Mexico

Itzel Anahi Martinez, MD

• Vargas, Ana Sofia, Operadora de Hospitales Angeles SA de CV, Ciudad de Mexico, Ciudad de México, Mexico

Ana Sofia Vargas, MD

• Muñoz, Victor Morales, Operadora de Hospitales Angeles SA de CV, Ciudad de Mexico, Ciudad de México, Mexico

Victor Morales Muñoz, MD

• Sanchez Perez, Maria Jose, Operadora de Hospitales Angeles SA de CV, Ciudad de Mexico, Ciudad de México, Mexico

Maria Jose Sanchez Perez, MD

• Sanchez Rodriguez, Cristopher Candido, Operadora de Hospitales Angeles SA de CV, Ciudad de Mexico, Ciudad de México, Mexico

Cristopher Candido Sanchez Rodriguez, MD

• Hernandez Flores, John, Operadora de Hospitales Angeles SA de CV, Ciudad de Mexico, Ciudad de México, Mexico

John Hernandez Flores, MD

Introduction

Mycobacterium tuberculosis (MTB) is an intracellular pathogen with a wide range of clinical manifestations, including interstitial nephritis (IN) . Diagnosing IN due to MTB can be challenging, as non-invasive tests like QuantiFERON and GeneXpert may yield negative in some cases. Renal biopsy (Rb) remains the gold standard.

Case Description

A 61-year-old man with a urothelial cancer treated with lymphadenectomy and bladder resection with robotic neo-bladder creation in March 2023. He finished at july 2023 gemcitabine and cisplatin with a GFR of 80,free tumor activity. Four months after, he presented weakness and weight loss. His creatinine up over two months along with leukocyturia, hematuria, glycosuria, and proteinuria. He presented at hospital with hemodialysis emergency and severe anemia (normal transferrin receptor/elevated ferritin levels). US reported a small right kidney and an enlarged left one, indicating a high risk for Rb. Infectious and autoimmune tests were performed (Figure 1). He recieved 3x methylprednisolone boluses and rapid tapering. The Rb showed granulomas, severe tubular damage, and ZN positive bacilli, 50% fibrosis and tubular atrophy. The patient started third-line anti-MTB: rifampicin, isoniazid, clarithromycin, levofloxacin, linezolid, and amoxiclav for two months induction. The last GFR is 30 and continue improving since he discontinued hemodialysis in the first month.

Discussion

Rb remains the gold standard for diagnosing MTB-induced IN, even in patients with negative non-invasive test results. Early diagnosis and treatment are essential for improving the prognosis of patients with this disease.