Atypical Presentation of Pyelonephritis in a Crohn’s Disease Patient on Adalimumab

Abstract

Introduction: Anti-TNF (tumor necrosis factor) agents such as infliximab or adalimumab are used as monotherapy or in conjunction with other medications in the treatment of patients with moderate-to-severe Crohn’s disease (CD) who failed to respond to first-line therapy with mesalamine and/or corticosteroids. Nevertheless, these agents have consistently been linked to an increased risk of granulomatous infection, particularly TB, as well as to an increase in overall infections. The following case illustrates this risk in a young woman with CD on adalimumab with an atypical presentation of pyelonephritis. Case Report: A 25-year-old African American woman with CD maintained on adalimumab and mesalamine complicated by perianal disease, colonic strictures status post segmental colectomy with colonic anastomosis presenting with worsening left-sided crampy abdominal pain of 3 days duration, associated with nausea, vomiting, decreased PO intake, and a bloody, mucoid diarrhea consistent with her previous CD flares. The patient had no urinary symptoms. On physical exam, she was afebrile, hemodynamically stable, and in no acute distress. The GI exam revealed diffuse abdominal tenderness with no rebound or guarding, and normoactive bowel sounds. The patient had no CVA tenderness. Laboratory studies showed no leukocytosis, a normal lactate, and a UA with 9 WBCs/hpf. A CT scan of the abdomen and pelvis with contrast revealed multifocal bilateral pyelonephritis with cystitis. The urine culture then grew >100,000 CFUs/mL Proteus mirabilis and 50,000 CFUs/mL Escherichia coli. The patient was then started on antibiotics treating her bilateral pyelonephritis and cystitis. Discussion: This case illustrates how patients on immunosuppressive therapy such as adalimumab are not only at an increased risk for infections, but can also atypically manifest their infections given their inability to mount an adequate immune response. The patient presented in the case had nearly absent signs and symptoms of pyelonephritis including leukocytosis, fever, urinary symptoms, and CVA tenderness on physical exam. Moreover, the patient had only very mild pyuria with 9 WBCs/hpf. TNF is a proinflammatory cytokine that is important in the human immune response to infection. It is released by T lymphocytes, activated macrophages and other immune cells in response to a variety of infectious stimuli. TNF plays a role in antitumor and antiviral activity, and mediates systemic inflammatory responses to infection and sepsis. Infections with opportunistic pathogens such as Listeria spp., Coccidiodes immitis, Aspergillus spp., Histoplasma capsulatum, Nocardia spp., and Mycobacteria, as well as routine bacterial pathogens such as Streptococci have been reported.