{"doi":"10.1093/cid/ciae179","title":"When Location and Timing Are at the Heart of the Diagnosis","abstract":"Question: A 27-year-old man, who had grown up on a livestock farm in Mexico, presented to the hospital with a 3-month history of left neck pain, abdominal pain, and weight loss. Computed tomographic (CT) imaging showed widespread lymphadenopathy and mild abdominopelvic ascites. Human immunodeficiency virus (HIV) testing was positive, and laboratory studies revealed an HIV type 1 (HIV-1) plasma RNA of 707 000 copies/mL and CD4 count of 21 cells/µL. He denied any known exposure to individuals with tuberculosis. A biopsy of a cervical lymph node was performed, and a Fite stain performed on this specimen is presented in Figure 1. A sputum sample was obtained and grew an organism with a similar morphology on acid-fast staining. He was initiated on rifampin, isoniazid, pyrazinamide, and ethambutol followed by antiretroviral therapy 8 days afterward. He subsequently developed worsening symptoms along with fevers and tachycardia 2 weeks later. He endorsed adherence to all his medications. He was referred to our institution for clinical protocol participation. His HIV-1 plasma RNA level was 101 copies/mL, CD4 count was 105 cells/µL, C-reactive protein was 50.4 mg/L, and ferritin was 1337 µg/L. A research positron emission tomography (PET)–CT scan was completed and is presented in Figure 2. Fite stain from cervical lymph node biopsy. The two black arrows indicate bacilli-shaped organisms staining magenta-pink, consistent with an acid-fast organism. Positron emission tomography–computed tomographic images of the body. What is your diagnosis? Diagnosis: Disseminated Mycobacterium bovis complicated by immune reconstitution inflammatory syndrome (IRIS). DNA extraction was performed on the isolate from the sputum culture, and a multiplex polymerase chain reaction assay was performed on the sample to differentiate Mycobacterium tuberculosis from M. bovis (Figure 3) [1]. This revealed the causative organism to be M. bovis. The patient additionally developed dysuria, and an acid-fast stain on a urine sample revealed acid-fast bacilli. No organisms were isolated by mycobacterial culture on a repeat sputum sample or on 4 separate urine samples. Additional infectious workup was unremarkable. His clinical course was therefore thought to be most consistent with IRIS secondary to disseminated M. bovis. Differentiation polymerase chain reaction (PCR) assay for Mycobacterium tuberculosis versus Mycobacterium bovis. Primer CBS1 is common for both M. tuberculosis and M. bovis. Primer CBS2 is specific for M. bovis, and CBS3 is specific for M. tuberculosis and other non-bovis species. Lane 1: Sample obtained by DNA extraction from a sputum sample from this patient. Lane 2: M. bovis–positive control. Lane 3: M. tuberculosis–positive control. Lane 4: negative control. The positive band seen in lane 1 on the CBS1/CBS2 primers correspond to the band seen in lane 2, whereas there are no bands seen in lane 1 with the CBS1/CBS3 primers; test sample identification is therefore consistent with M. bovis. In addition to the previously noted lymphadenopathy on CT imaging, PET-CT imaging (Figure 2) displayed widespread peritoneal involvement with increased uptake around the liver and spleen, as well as focal areas of increased uptake in the kidneys and T11–T12 thoracic spine. Increased pathologic metabolic activity on PET-CT imaging has been previously reported to be associated with IRIS development and to correlate with inflammatory biomarkers [2]. Corticosteroids had been initiated, pyrazinamide was discontinued, and the patient initiated moxifloxacin. He displayed improvement in his fever curve, tachycardia, and inflammatory markers over the subsequent 3 weeks and was discharged home. He continued treatment for IRIS with tapering doses of corticosteroids. At 6 months’ follow-up, he had resolution of the neck pain, abdominal pain, and dysuria. Mycobacterium bovis is a zoonotic infection that primarily affects bovine animals but may be transmitted to humans through co","journal":"Clinical Infectious Diseases","year":2024,"id":503812,"datarank":0.0,"base_score":0.0,"endowment":0.0,"self_citation_contribution":0.0,"citation_network_contribution":0.0,"self_endowment_contribution":0.0,"citer_contribution":0.0,"corpus_percentile":null,"corpus_rank":null,"citation_count":0,"citer_count":0,"citers_with_citation_signal":0,"citers_with_endowment":0,"datacite_reuse_total":0,"is_dataset":false,"is_dataset_confidence":0.9485,"is_data_producer":false,"deposit_databanks":null,"is_oa":true,"file_count":0,"downloads":0,"has_version_chain":false,"published_date":"2024-01-01","fair_score":null,"fair_percentile":null,"algorithm_id":"datarank_citation_only_1hop_v6","ranking_scope":"data_only","authors":[{"id":431963,"name":"Maura Manion","orcid":"0000-0003-0991-0011","position":1,"is_corresponding":false},{"id":342096,"name":"Elizabeth Laidlaw","orcid":"0000-0001-8241-6859","position":2,"is_corresponding":false},{"id":1354396,"name":"Michael Holman","orcid":null,"position":3,"is_corresponding":false},{"id":484972,"name":"Mayank Patel","orcid":"0000-0002-6609-5394","position":4,"is_corresponding":false},{"id":241760,"name":"Irini Sereti","orcid":"0000-0002-0076-0224","position":5,"is_corresponding":false},{"id":863585,"name":"Brian Epling","orcid":"0000-0002-7434-942X","position":0,"is_corresponding":true}],"reference_count":9,"raw_metadata":null,"created_at":"2026-07-19T02:10:35.597333Z","pmid":"39325646","pmcid":null,"fwci":null,"citation_percentile":null,"influential_citations":0,"oa_status":null,"license":null,"views":0,"total_file_size_bytes":0,"version_count":0,"fair_f":null,"fair_a":null,"fair_i":null,"fair_r":null,"fair_zscore":null,"fair_rationale":null,"fair_model":null,"fair_agent_version":null,"fair_fulltext_source":null,"fair_has_llm":null,"fair_computed_at":null,"clinical_trials":[],"software_tools":[],"db_accessions":[],"linked_datasets":[],"topics":[]}