Disseminated Mycobacterium Avium Complex Infection Research Articles

An Uncommon Cause of Elevated Liver Transaminases: Immune Reconstitution Inflammatory Syndrome from Unmasking of Occult Mycobacterium Avium Complex Infection in an HIV Infected Patient

Abnormal liver chemistry from the development of immune reconstitution inflammatory syndrome (IRIS) may reflect an unmasking of subclinical disease. We present the case of a 37-year-old female with a mixed pattern of liver injury from disseminated mycobacterium avium complex infection after starting antiretroviral therapy (ART). Presenting symptoms were fever, confusion, dysphagia, and abdominal discomfort for one week. Exam revealed a fever of 103.2°F, hypotension, encephalopathy, and abdominal tenderness. Lab work was significant for acute normocytic anemia, leukopenia, absolute CD4 count 28 cells/cmm, HIV viral load 276 viral copies/ml (vc/ml), ALT 267 U/L, AST 484 U/L, alkaline phosphatase 342 U/L, and normal total bilirubin. Imaging revealed hepatomegaly with steatosis and mesenteric and retroperitoneal lymphadenopathy. Percutaneous liver biopsy demonstrated noncaseating granulomas with AFB-positive organisms, with AFB blood cultures growing Mycobacterium avium complex (MAC), consistent with disseminated MAC infection. Clinicians must have a high index of suspicion for IRIS when determining the etiology of elevated liver transaminases in patients with HIV.

Disseminated Mycobacterium avium Complex Infection in a Patient Treated With Immunosuppressants

Mycobacterium avium complex (MAC) is an important cause of opportunistic infections in immunosuppressed hosts, such as patients with HIV infection and solid organ transplant recipients. MAC disease usually presents in 4 distinct clinical categories: chronic pulmonary disease, disseminated disease, skin/soft-tissue infection, and superficial lymphadenitis. However, clinical reports on gastrointestinal (GI) MAC disease are rare, especially in patients without HIV infection or a history of organ transplantation. We describe a case of non-HIV-associated GI MAC disease in a patient with long-term mycophenolate mofetil use. In this case, MAC organisms in the GI tract and ascites were observed. Endoscopy revealed a unique colonic image with large, deep epithelial denudations. This suggests that apart from patients with HIV infection or transplant recipients, those treated with immunosuppressants can have disseminated MAC. Therefore, internal physicians need to monitor patients undergoing mycophenolate mofetil immunosuppressant therapy.

When dyspnea is a Hickam’s Dictum

Synchronous opportunistic infections are luckily rare in people living with HIV (PLWH) in the era of highly effective antiretroviral medications. We describe the case of a middle-aged man who presented with diarrhea and shortness of breath and was found to have pneumocystis pneumonia, disseminated histoplasmosis and disseminated mycobacterium avium complex infection along with a new diagnosis of human immunodeficiency virus (HIV) infection. This case highlights that individuals who remain undiagnosed with HIV infection for a long time can still present with concurrent infections and clinicians should remain aware of this.

Epidural intracranial abscesses and multiple bone metastases caused by disseminated Mycobacterium avium complex infection: illustrative case.

Mycobacterium avium complex (MAC) generally causes localized pulmonary infections in immunocompromised hosts, but rarely in other organs and tissues, which is called disseminated MAC infection. The authors herein present a 48-year-old male patient with disseminated MAC infectious lesions in the lungs and on the cranial, vertebral, femoral, and pelvic bones, a normal CD4 count, and immunopositivity for the interferon-ɤ (IFN-ɤ) neutralization antibody. Cranial lesions were multiple osteolytic lesions associated with abscesses in the cranial bones. The patient initially received conservative treatment with multiple antibiotics; however, cranial lesions worsened. Therefore, multiple cranial lesions were removed via osteoplastic craniectomy and the postoperative course was uneventful. Pathological findings revealed MAC infection. The patient was discharged without recurrence or complications. Multiple cranial MAC dissemination with immunopositivity for the IFN-ɤ antibody is rare. The authors herein present the clinical course of a rare surgical case of MAC dissemination with a literature review.

S3402 Enterocolitis Caused by Mycobacterium Avium Complex in an HIV-Infected Patient

Introduction: Diarrhea in patients with human immunodeficiency virus (HIV) can be due to a variety of etiologies including infection, malignancy, and antiretroviral therapy (ART). With increased use of ART, diarrhea due to opportunistic infections has become less common. Here we report a rare case of chronic diarrhea due to Mycobacterium avium complex (MAC) infection involving the duodenum, colon, and rectum of a patient with advanced HIV. Case Description/Methods: A 41-year-old man with HIV infection diagnosed two years earlier presented with progressively worsening diarrhea. Two months prior, his CD4 count was stable at 50 cells/uL and his HIV level was undetectable while on dolutegravir/lamuvidine. He had history of MAC mycobacteremia under treatment with ethambutol, azithromycin, and rifabutin. He also had cytomegalovirus (CMV) viremia treated with valganciclovir. He reported compliance with the above medications. He had eight-month history of frequent, watery diarrhea associated with malaise, nausea, bloating, abdominal pain, and weight loss. He was hospitalized for severe malnutrition and electrolyte abnormalities. Evaluation of his diarrhea included negative C. difficile toxin, enteric pathogen panel, and ova and parasite exam. CMV was detected in the blood at 17,000 IU/mL and HIV viral load was 6,166 IU/mL. Esophagogastroduodenoscopy was performed and revealed diffuse erythema and edema affecting the mucosa of the entire duodenum with associated villous blunting and fissuring (Figure A). Flexible sigmoidoscopy revealed normal appearing mucosa to the level of the ascending colon. Pathology from duodenal biopsies showed extensive histiocytic inflammation with presence of acid-fast bacillus organisms (Figures B and C). Random biopsies from the colon and rectum showed similar findings and no evidence of CMV. Acid-fast bacillus blood cultures grew Mycobacterium avium-intracellulare. His MAC treatment was changed to amikacin, linezolid, rifampin, and ethambutol with subsequent improvement in his diarrhea. Discussion: Gastrointestinal tract involvement by MAC is usually part of a disseminated MAC infection in patients with advanced HIV, especially those with CD4 lymphocyte counts < 50 cells/uL. The duodenum is most often affected, followed by the rectum. We report this case to raise awareness that MAC enterocolitis remains an important etiology of chronic diarrhea in patients with advanced HIV.Figure 1.: A, EGD showing duodenal involvement by MAC causing diffuse erythema and edema with villous blunting and fissuring. B, H&E stain of duodenal mucosa with extensive histiocytic inflammation. C, Ziehl-Neelsen stain of duodenal mucosa with acid-fast bacillus positive organisms consistent with Mycobacterium avium complex.

The unique diagnostic and management challenge of a patient with concomitant anti-interferon-gamma autoantibody associated immunodeficiency syndrome, IgG4-related disease, and treatment refractory, disseminated mycobacterium avium complex infection

BackgroundAnti-interferon-gamma autoantibody-associated immunodeficiency syndrome is a rare and underrecognized adult onset immunodeficiency syndrome associated with severe opportunistic infections such as disseminated nontuberculous mycobacterium. Few cases have documented a relationship with IgG4-related disease. Concomitant diagnoses of these diseases present a diagnostic and management challenge.Case presentationA 61 year old man of Southeast Asian descent with pulmonary mycobacterium avium complex infection presented to our hospital system with a new skin rash and worsening lymphadenopathy. He was eventually diagnosed with IgG4-related disease through excisional nodal biopsy. He was managed with immunosuppressive treatment with prednisone, rituximab and cyclophosphamide. He later re-presented with disseminated mycobacterium avium complex infiltration of his joints, bones and prostate. Original titers of anti-interferon-gamma autoantibodies were falsely negative due to being on immunosuppressive therapy for his IgG4-related disease. However, anti-interferon-gamma autoantibody titers were re-sent after immunosuppression was held and returned strongly positive.ConclusionsThis case reviews diagnostic criteria and discusses management strategies with existing challenges in treating a patient with concomitant adult onset immunodeficiency syndrome, IgG4-related disease and a disseminated mycobacterial avium complex infection.

Multiple opportunistic infections (pulmonary tuberculosis, Mycobacterium avium complex and parvovirus B19) in a single patient

IntroductionHIV infection is a common disease in the South African population. The virus can lead to the development of many opportunistic infections. This case study examines co-infection with three opportunistic infections and the need for clinical suspicion of infections in our HIV population.Patient presentationA 36-year-old unemployed female residing in Soweto, Johannesburg, presented at Chris Hani Baragwanath Hospital (CHBAH). She was HIV positive, defaulting treatment, with no other comorbidities. She presented to CHBAH with general body weakness, diarrhoea, cough and constitutional symptoms; clinically she appeared pale and chronically ill. A differential diagnosis was made of multiple infections co-inhabiting the patient.Management and outcomeThe patient had blood, sputum, radiological and invasive bone marrow aspiration, and trephine biopsies completed. The investigations revealed that she was co-infected with Mycobacterium tuberculosis (MTB), Mycobacterium avium complex (MAC) and parvovirus B19. The TB and disseminated MAC infection were managed with rifampicin, isoniazid, ethambutol, pyrazinamide and azithromycin, and reinitiation of antiretroviral (ARV) treatment was planned on further follow-up of the ARV drug resistance test. The parvovirus B19 infection was managed with immunoglobulins (Polygam) and steroids (prednisone). She was discharged successfully for further follow-up.ConclusionA thorough history, clinical examination and subsequent targeted investigations are vital to arriving at the correct diagnosis or diagnoses. The case presented above serves to illustrate how three life-threatening opportunistic infections (OIs), all with differing treatments, may present in a single patient. Clinicians caring for immunosuppressed patients need to remain vigilant for the presence of multiple OIs occurring simultaneously.

830. Central Nervous System Involvement in Disseminated Mycobacterium avium Complex Infection in Patients with Newly Diagnosed HIV

BackgroundDisseminated Mycobacterium avium complex (MAC) infection occurs in 20-40% of patients with < 50 CD4/mm3. Data describing central nervous MAC involvement (CNS-MAC) in disseminated infection is scarce. MethodsWe conducted a retrospective case series in the outpatient infectious diseases clinic in the hospital “Dr. Manuel Gea Gonzales” in Mexico City. We reviewed all records from October 2020 to May 2021 and identified all culture proven MAC infections.ResultsWe found 7 cases of MAC, with disseminated infection (positive bone marrow cultures) with 3 out of those 7 meeting our definition for CNS-MAC (positive cerebrospinal fluid culture). All cases of CNS-MAC infection occurred in patients with < 50 CD4/mm3 and recent HIV diagnosis (1-4 months) that were referred to our institution with consumptive syndrome and fevers. All patients were receiving antiretroviral treatment (ART) with BIC/FTC/TAF and initiated ART in less than 1 month since HIV diagnosis. Opportunistic infections were ruled-out at the moment of CNS-MAC diagnosis (criptococcal meningitis, cytomegalovirus retinitis, tuberculosis and histoplasmosis). All patients exhibited non-specific neurologic symptoms at arrival (headache and bradipsiquia) mixed with more severe symptoms (one case of ataxia, one case of vertigo, one case of III nerve palsy). All patients were treated with Clarithromycin/Levofloxacin/Ethambutol. Two patients achieved symptom remission and 1 patient was lost to follow-up. Of important note, all CSF analysis and CNS imaging studies carried-out were normal. No MAC bacilli were identified with direct Ziel-Neelsen staining of CSF.ConclusionWe found a high proportion of CNS-MAC in patients with disseminated MAC infection (42.8%) during the study period. All patients presented CNS symptoms and normal CSF characteristics. In our setting, patients with suspected disseminated MAC infection CD4 counts < 50 cells/mm3 might represent a specific population that could benefit from routine targeted diagnostic test at presentation in order to establish CNS involvement.Disclosures All Authors: No reported disclosures

Protein-losing enteropathy caused by disseminated Mycobacterium avium complex infection in a patient receiving antiretroviral therapy: an autopsy case report

BackgroundDisseminated Mycobacterium avium complex infection is an important indicator of acquired immunodeficiency syndrome (AIDS) in patients with advanced human immunodeficiency virus (HIV) infection. Effective antiretroviral therapy has dramatically reduced the incidence of and mortality due to HIV infection, although drug resistance and poor medication adherence continue to increase the risk of disseminated M. avium complex infection. However, gastrointestinal lesions in cases of disseminated M. avium complex infection resulting in protein-losing enteropathy have been rarely discussed. Therefore, we present a case of protein-losing enteropathy caused by disseminated M. avium complex infection in a patient undergoing antiretroviral therapy.Case presentationA 29-year-old man was diagnosed with AIDS 4 years ago and was admitted for a 10-month history of refractory diarrhea and fever. Despite receiving antiretroviral therapy, the viral load remained elevated due to poor medication adherence. The patient was diagnosed with disseminated M. avium complex infection and started on antimycobacterial drugs 2 years before admission. However, the infection remained uncontrolled. The previous hospitalization 1 year before admission was due to hypoalbuminemia and refractory diarrhea. Upper gastrointestinal endoscopy revealed a diagnosis of protein-losing enteropathy caused by intestinal lymphangiectasia, and treatment with intravenous antimycobacterial drugs did not resolve his intestinal lymphangiectasia. The patient inevitably died of sepsis.ConclusionsClinical remission is difficult to achieve in patients with AIDS and protein-losing enteropathy caused by disseminated M. avium complex infection due to limited options of parenteral antiretroviral drugs. This report highlights the importance of identifying alternative treatments (such as an injectable formulation) for patients who do not respond to antiretroviral therapy due to protein-losing enteropathy with disseminated M. avium complex infection.

Disseminated Mycobacterium avium Complex Infection Causing Multiple Skull Defects in an Immunocompetent Patient: A Case Report

Mycobacterium avium complex (MAC) infection mainly causes pulmonary disease. However, in 20% to 30% of cases, it also induces various extrapulmonary diseases. Disseminated MAC infection occasionally occurs in immunocompromised patients but very rarely in immunocompetent patients. An 80-year-old immunocompetent woman presented with multiple chronic wounds on the scalp that had not improved despite prolonged treatment. A scalp abscess caused by disseminated MAC infection 4 years ago had gone through repeated cycles of improvement and aggravation despite continued use of anti-mycobacterial agents and active wound care. Enhanced brain computed tomography and magnetic resonance imaging revealed multiple skull defects and abscesses invading the dura mater. Under general anesthesia, the infected scalp skin and bone were sufficiently removed, and the bone and soft tissue defects were repaired with cranioplasty using a titanium mesh plate and local flap. As exemplified in this case, multiple chronic wounds unresponsive to treatment need to be screened for MAC infection. As chronic MAC infection in the scalp can cause skull destruction and brain infection, it needs to be treated aggressively at an early stage to prevent serious morbidity and mortality. Effective MAC infection management involves adequate medication, regular follow-up imaging, and active surgical procedure.

TB or NTM: Can a new multiplex PCR assay be the answer?

TB or NTM: Can a new multiplex PCR assay be the answer?

Hypercalcemia: A Metabolic Complication of an AIDS-Defining Illness

Abstract Background: Hypercalcemia may result from the activation of macrophages in granulomatous diseases with increased production of 1,25 dihydroxyvitamin D/calcitriol. Its occurrence in patients with human immunodeficiency virus-1 (HIV-1) infection may be atypical and signal major changes in immune status. We report on a patient with acquired immunodeficiency syndrome (AIDS) presenting with new-onset hypercalcemia after months of treatment for mycobacterium avium complex (MAC) infection and normal calcitriol levels. Clinical Case: A 37-year-old man on treatment for HIV-1 and disseminated MAC infection presented to the hospital 6 months after initial diagnosis with worsening headache, cough, and abdominal pain. On arrival he was afebrile and without palpable lymphadenopathy. He was found to have a high serum calcium (13.4 mg/dL, n 8.6–10.6 mg/dL) and acute kidney injury (AKI) (creatinine 4 mg/dL, n 0.6–1.25 mg/dL). His CD4 count had increased from 24 at time of diagnosis to 162 cells/μL (n 410–1,590 cells/μL); his HIV viral load was undetectable. Workup for hypercalcemia revealed an elevated phosphorus (5.2 mg/dL, n 2.5–5.0 mg/dL), low 25-OH vitamin D level (&amp;lt;13 ng/mL, n 25–80 ng/dL), low PTH (4.8 pg/mL, n 12–88 pg/mL), and calcitriol level of 31.4 pg/mL, n 19.9–73.3 pg/mL). Additional tests, including serum electrophoresis, thyroid stimulating hormone, and parathyroid hormone-related peptide levels, were unremarkable. The patient was diagnosed with hypercalcemia secondary to dysregulated calcitriol production in the setting of disseminated MAC and possible immune reconstitution. Hypercalcemia resolved with hydration and prednisone 20 mg daily. Patient was discharged with an 8-day prednisone taper, but readmitted to the hospital 3 weeks later with recurrent hypercalcemia (13.8 mg/dL) and AKI. Urine calcium was found to be elevated (484 mg/24 hours, n100-300 mg/24 hours) and repeat calcitriol was 53.6 pg/ml. Patient was restarted on prednisone 40 mg daily with normalization of calcium within 5 days (calcium 10.3 mg/dL). Conclusion: Hypercalcemia due to increased calcitriol production in the setting of MAC infection, an AIDS-defining illness, may occur months after initiation of effective antibiotic and antiviral therapy and could represent a manifestation of immune reconstitution. The deleterious effects of excess calcitriol may be present even in patients with chronic vitamin D deficiency and a calcitriol level that inappropriately remains within the normal range.

Disseminated mycobacterium avium complex infection mimicking lymphoproliferative disorder in a kidney transplant recipient

Disseminated mycobacterium avium complex infection mimicking lymphoproliferative disorder in a kidney transplant recipient

S1773 Not Your Typical Diarrhea: A Case of Disseminated MAC in a Solid Organ Transplant Recipient

INTRODUCTION: Mycobacterium avium complex (MAC) colitis is a rare complication of immunosuppression in solid organ transplant (SOT) recipients. Here, we describe a case of disseminated MAC infection with colitis following simultaneous pancreas-kidney (SPK) transplantation. CASE DESCRIPTION/METHODS: A 54-year-old female was admitted to the hospital with a two-month history of watery diarrhea, intermittent nausea and unintentional weight loss of 40-pounds. She was recently discharged after a prolonged hospital stay for management of acute diarrhea and was diagnosed with recurrent Clostridium difficile Infection (CDI) that required multiple courses of fidaxomicin as she was intolerant to vancomycin. Past medial history included SPK transplant 4 years ago complicated by allograft rejection, CMV viremia and recurrent CDI. Her immunosuppressive regimen included mycophenolic acid, sirolimus, prednisone, and tacrolimus with therapeutic range drug levels. Laboratory examination was remarkable for leukopenia of 1.7 × 109/L with absolute neutrophil count (ANC) of 1300 cells/µL and otherwise normal chemistries. Initial infectious work-up unremarkable including CMV PCR, BK Virus PCR, C diff toxin and antigen and infectious stool studies. Computed tomography showed mild esophageal thickening without any colitis. Colonoscopy showed few patchy erosions dispersed throughout the colon. Histologic examination of random colon biopsies revealed poorly formed granulomas that stained positively for acid fast bacilli (AFB). Esophagogastroduodenoscopy was unremarkable except LA grade D esophagitis and biopsies were obtained from the duodenum. Interestingly, these duodenal biopsies also showed granulomas that stained positive for AFB. AFB culture performed on all specimens was positive for MAC. MAC was also isolated from urine and stool cultures that were reported later. Patient was started antimicrobial therapy with ethambutol, rifampin, and azithromycin guided by infectious disease specialist with resolution of diarrhea and weight gain. DISCUSSION: MAC infections are well established in acquired immunodeficiency virus infection, but remain rarely reported in SOT recipients. Moreover, disseminated MAC presenting as diarrhea is even more uncommon. The causes of diarrhea are exhaustive in patients on immunosuppression and hence it is important to keep MAC in the differential as its diagnosis is challenging and requires tissue sampling with culture and gene sequencing. Antimicrobials provide effective treatment and eradication.

S2790 Mycobacterium avium Complex Enteritis Mimicking Whipple's Disease in a Patient With Advanced AIDS

INTRODUCTION: Acquired Immunodeficiency Syndrome (AIDS) patients are susceptible to numerous opportunistic infections, including Mycobacterium avium complex (MAC). MAC infection usually presents as a disseminated disease with fever, nights sweats, diarrhea as well as lymphadenopathy which can be the presenting symptoms of various other diseases, such as Whipple's disease (WD). We present a case of MAC infection initially diagnosed as Whipple’s Disease in a patient resulting in delay in MAC treatment. CASE DESCRIPTION/METHODS: A 37 year old homosexual male presented with a one year history of progressively worsening abdominal pain accompanied by intermittent non bloody, non bilious vomiting, chronic diarrhea, fatigue and 60 lbs unintentional weight loss over several months. He underwent an elective EGD where abnormal appearing duodenal mucosa was seen with duodenal biopsy showing villous atrophy and period acid Schiff (PAS) stain positive macrophages, while abdominal imaging showed retroperitoneal and mesenteric lymphadenopathy (Image 1). Despite initiation on treatment for WD, he continued to clinically decline. Given his high risk social history and significant constitutional symptoms, HIV infection was considered as an alternative diagnosis. He was found to have HIV/AIDS (viral load of >100,000 copies/mL and CD4 count 9/μL) and blood cultures positive for MAC. On further review, his duodenal biopsies were positive for acid fast bacillus (AFB) confirming MAC enteritis. A CT chest revealed a 4.6 cm right lung mass with biopsy positive for AFB stain(Image 2). Patient was then initiated on appropriate treatment for disseminated MAC infection (azithromycin, rifabutin, ethambutol) as well as antiretroviral therapy resulting in clinical improvement. DISCUSSION: The differential diagnoses for villous atrophy include malabsorptive diseases, infections, malignancy, pancreatic insufficiency but other less common infectious entities such as MAC should be considered in the right clinical settings. MAC infections have become increasingly uncommon since the advent of highly effective antiretroviral therapy, control of HIV infection and appropriate antimicrobial prophylaxis. Due to the relative rarity, diagnosis and treatment may be delayed, especially when presenting symptoms are non-specific, which can result in morbidity and mortality.Figure 1.: View of duodenum during endoscopy which shows white color plaques in the second and third part of the duodenum (A). H&E stain (20X) of duodenal biopsy shows mildly blunted villi due to expansion of lamina propria by foamy macrophages in a patchy fashion (B). No fat vacuoles or increased intraepithelial lymphocytes seen. AFB stain (20X) of duodenal biopsy shows many positive bacillary forms confirming the presence of Mycobacterium avium intracellular complex (C). Abdominal lymphadenopathy noted on computed tomography of abdomen (red circle) (D).Figure 2.: Computed Tomography of Lung mass (red circle) (A). H&E stain (40X) lung mass biopsy shows florid lympho-histiocytic reaction (B) while CD68 stain (40X) shows many macrophages (C), and AFB stain (40X) confirms presence of mycobacterial organisms (D).

Disseminated Mycobacterium avium complex infection as a differential diagnosis of tuberculosis in HIV patients.

BACKGROUND: Disseminated Mycobacterium avium complex infection (DMAC) has symptoms and microscopic findings similar to those of TB in HIV patients. To inform a clinical algorithm-based differential diagnosis, we aimed to characterise the clinical features of DMAC.METHODS: This was a retrospective cohort study of 192 HIV-positive patients with culture-confirmed mycobacterial infections hospitalised during 1996-2016 at a major HIV/AIDS treatment centre in Taiwan.RESULTS: HIV patients with DMAC (n = 58) had a three times higher 1-year mortality than those with TB (n = 98) (48.3% vs. 16.3%, P < 0.001). DMAC and TB were not distinguishable by the WHO TB screening criteria (fever, cough, night sweats or weight loss). Nevertheless, DMAC was characterised by a lower median CD4 count (5.0 cells/µL vs. 38.5 cells/µL, P < 0.001), lower median body mass index (BMI) (17.7 kg/m² vs. 19.7 kg/m², P = 0.002) and the absence of chest radiographic findings (P < 0.001). Simultaneous presence of CD4 <20 cells/µl, BMI <18.5 kg/m² and negative chest radiographic finding had a 98% specificity for diagnosing DMAC against TB or other types of mycobacterial infections.CONCLUSION: DMAC is an important differential diagnosis of TB in HIV patients. A simple rule based on CD4, BMI and chest radiography may inform the decision to start anti-DMAC treatment in patients with mycobacterial infection.

Disseminated Mycobacterium avium complex infection mimicking malignancy in a patient with anti-IFN-\u03b3 autoantibodies: a case report

BackgroundDisseminated nontuberculous mycobacteria (NTM) infections occur mostly in immunocompromised patients. Therefore, it is difficult to diagnose disseminated NTM infections in patients without history of immunocompromised diseases or using immunosuppressant. Patients with anti-interferon-γ (IFN-γ) autoantibodies are vulnerable to intracellular infections, such as disseminated NTM. Currently, there is no widely used and efficient technique for the detection of anti-IFN-γ autoantibodies. Herein, we report a case of an apparently healthy patient with disseminated Mycobacterium avium complex (MAC) infection who tested positive for anti-IFN-γ autoantibodies.Case presentationA 64-year-old non-immunocompromised and apparently healthy Asian male presented to the emergency department with complaints of progressive chest pain for about 6 months and weight loss. A bulging tumour was found in the anterior chest wall. Chest computed tomography showed a lung mass over the right lower lobe and an osteolytic lesion with a soft tissue component at the sternum. Sonography-guided biopsies for the osteolytic lesion and sputum culture confirmed the presence of disseminated MAC infection. In addition, positive test result of anti-IFN-γ autoantibodies was noted. The patient was prescribed antibiotics. The lesions over the right lower lobe and sternum attenuated following the antibiotic treatment.ConclusionDetection of anti-IFN-γ autoantibodies is important among previously healthy people with disseminated NTM infection. Presence of anti-IFN-γ autoantibodies may suggest a high risk of severe intracellular infection, such as disseminated NTM infection.

377. Diagnostic Yield of Bone Marrow Aspiration and Biopsy in Human Immunodeficiency Virus Patients with Fever and/or Cytopenia

BackgroundHuman Immunodeficiency Virus (HIV) patients are at increased risk of opportunistic infections and malignancies. Evaluation for the etiology of fever and/or cytopenia with conventional means such as cultures and serology can remain negative. Bone marrow aspiration or biopsy (BMAB) has the advantage of diagnosing disseminated infections, hematological abnormalities and oncological malignancies in HIV patients.MethodsWe performed a retrospective descriptive study of HIV patients with fever and/ or cytopenia who underwent Bone marrow aspiration or biopsy (BMAB). Patients with a diagnosis of HIV, 18 years and older who underwent BMAB in University Health (UH) Hospital or in UH clinics from January 2012 to February 2018 were included.ResultsThere were a total of 42 patients who underwent Bone Marrow Aspiration or Biopsy. The median age was 41.5 years. Twenty-eight patients were Male and 14 were female. Preexisting Hematological malignancy was present in 10 patients at the time of BMAB. Average CD4 count at the time of BMAB was 92. 8 patients were compliant with ART and 12 patients were compliant with clinic appointments. White Blood Cell (WBC) count below 4.4 cells / L was present in 30 patients at the time of BMAB. Disseminated Mycobacterium Avium Complex infection (2 patients),Disseminated Histoplasmosis (2 patients), Disseminated Cryptococcus (1 patient) and Parvovirus B19 (based on Immunohistochemistry, 1 patient) were diagnosed from BMAB. CD4 count of these 6 patients range from 0 to 12 at the time of BMAB. All 6 patients presented to the hospital with fever for evaluation. Average WBC count, Hemoglobin and platelet count in these patients are 4.1 cells / liter, 8.7 g/dL and 74.8 k/micro liter, respectively. All 6 patients were non compliant to HIV medications and clinic appointments.ConclusionSince the advent of Anti Retroviral drugs with excellent efficacy and early diagnosis of HIV patients, incidence of disseminated fungal and mycobacterial infections have decreased in the United States. But patients with low CD4 count and cytopenias warrant a Bone Marrow aspiration or Biopsy to make a clear and early diagnosis.Disclosures All authors: No reported disclosures.

A young boy with disseminated Mycobacterium avium complex infection

The case of a Chinese boy with no medical history, who presented with diarrhea and weight loss of 14-month duration and rashes and fever or 6-month duration, is described. The patient was finally diagnosed with disseminated Mycobacterium avium complex infection by skin biopsy and tissue culture. This case shows that Mycobacterium avium complex infection should be considered even in an immunocompetent patient with diarrhea and skin lesions.

Effect of Macrolide Prophylactic Therapy on AIDS-Defining Conditions and HIV-Associated Mortality.

Mycobacterium avium complex prophylaxis is recommended for patients with advanced HIV infection. With the decrease in incidence of disseminated Mycobacterium avium complex infection and the availability of antiretroviral therapy (ART), the benefits of macrolide prophylaxis were investigated. This study examined the impact of macrolide prophylaxis on AIDS-defining conditions and HIV-associated mortality in a cohort of HIV-infected patients on ART. Patients from TREAT Asia HIV Observational Database (September 2015 data transfer) aged 18 years and older with a CD4 count <50 cells/mm at ART initiation were included. The effect of macrolide prophylaxis on HIV-associated mortality or AIDS-defining conditions (as a combined outcome) and HIV-associated mortality alone were evaluated using competing risk regression. Sensitivity analysis was conducted in patients with a CD4 <100 cells/mm at ART initiation. Of 1345 eligible patients, 10.6% received macrolide prophylaxis. The rate of the combined outcome was 7.35 [95% confidence interval (CI): 6.04 to 8.95] per 100 patient-years, whereas the rate of HIV-associated mortality was 3.14 (95% CI: 2.35 to 4.19) per 100 patient-years. Macrolide use was associated with a significantly decreased risk of HIV-associated mortality (hazard ratio 0.10, 95% CI: 0.01 to 0.80, P = 0.031) but not with the combined outcome (hazard ratio 0.86, 95% CI: 0.32 to 2.229, P = 0.764). Sensitivity analyses showed consistent results among patients with a CD4 <100 cells/mm at ART initiation. Macrolide prophylaxis is associated with improved survival among Asian HIV-infected patients with low CD4 cell counts and on ART. This study suggests the increased usage and coverage of macrolide prophylaxis among people living with HIV in Asia.