Severe gastrointestinal hemorrhage due to Mycobacterium avium complex in a patient receiving immunosuppressive therapy

A Rare Case of Disseminated Mycobacterium avium-intracellulare Presenting as Proctitis

Mycobacterium avium intracellulare (MAI) infections are common in Human Immuno-deficiency Virus (HIV) positive patients. MAI infection can have localized or disseminated presentation, patients with low CD4 count presenting with disseminated infection. Fever, abdominal pain, diarrhea, and weight loss are generally the presenting symptoms of disseminated MAI. We present a rare case of a patient with HIV and low CD4 count presenting with proctitis as manifestation of disseminated MAI infection. A 25 year-old-man with HIV came to the emergency room (ER) with complaints of intermittent rectal bleeding for two months. His CD4 count was less than 20 cells/µL. He was MSM (men having sex with men) and has receptive anal intercourse with men. His stool work-up was unrevealing for infectious etiology. Swabs for gonorrhea and chlamydia were negative. Colonoscopy revealed erythematous, congested, friable rectal mucosa with two superficial ulcers. Biopsies of the ulcer were positive for acid fast staining bacteria and the culture grew MAI. His blood culture was negative for growth of acid-fast bacteria (AFB). However, liver biopsy performed for elevated alkaline phosphatase of 958 units/L revealed noncaseating granuloma. Gastro-duodenoscopy with duodenal biopsy did not reveal any mucosal abnormality. He was managed as with disseminated MAI infection using clarithromycin, ethambutol, and rifabutin in addition to HAART therapy. Interval Colonoscopy in 20 months showed resolution of rectal ulcer. The gut is often involved in patients with disseminated MAI infection, with the duodenum being the most common site. MAI infection should be suspected as possible etiology for proctitis in HIV positive patient with low CD4 count, as proctitis, though infrequent can be the sole presentation for disseminated MAI infection in patients with HIV and low CD4 count.

Proctitis Caused by Mycobacterium avium-intracellulare in an HIV-Infected Patient

Infectious proctitis is usually associated with sexually transmitted diseases, especially in HIV-infected individuals. Limited information is found about the role of Mycobacterium avium-intracellulare as a causative agent for this condition. Here, we report the case of an HIV-infected patient with a CD4 count of 304 cells/uL and undetectable HIV viral load, who presented with constipation and painful defecation. Endoscopic evaluation was significant for shallow rectal ulcerations. Histopathology revealed poorly formed granulomas. Stool culture grew Mycobacterium sp. that was further identified as Mycobacterium avium-intracellulare by DNA probe. He was successfully treated with a 3-drug regimen that included azithromycin, ethambutol and rifabutin. We advocate the use of AFB stool culture in cases of proctitis in which initial investigations for sexually transmitted diseases are unrevealing.

Complete Remission of Minimal Change Disease Following an Improvement of Lung Mycobacterium avium Infection

A 46-year-old woman suddenly developed peripheral edema. Her massive proteinuria, hypoproteinemia, and renal biopsy findings yielded the diagnosis of minimal change disease (MCD). In addition, lung Mycobacterium avium infection was diagnosed according to a positive culture of her bronchoalveolar lavage fluid. The lung lesion was improved by anti-nontuberculous mycobacteria therapy. Surprisingly, her proteinuria also gradually decreased and she attained complete remission of MCD without any immunosuppressive therapy. She has subsequently remained in complete remission. We herein report an interesting case of MCD with lung Mycobacterium avium infection, suggesting a causal relationship among infection, immune system abnormality, and MCD/nephrotic syndrome.

[Unusual cause of abdominal lymphomas]

A 72 year old HIV-negative patient without relevant immunosuppression presented with abdominal lymphomas and inflammatory signs in the colon. Mycobacterium intracellulare was grown from colonic biopsies and stool. There was no sign of malignancy or chronic inflammatory bowel disease. We diagnosed an atypical, gastrointestinal mycobacteriosis und treated the patient accordingly. This led to a good response.

Rapidly progressive glomerulonephritis associated with nontuberculous mycobacteria

A 72-year-old woman with a past medical history of nontuberculous mycobacteria (NTM) pulmonary disease was admitted because of hemoptysis and acute renal failure. A chest X-ray showed interstitial infiltration over bilateral lung fields. Kidney biopsy showed immune complex-mediated acute diffuse proliferative glomerulonephritis with 48% crescents and glomerular endocapillary hypercellularity with exudative neutrophils suggestive of infection-related glomerulonephritis. Reactivated NTM infection of the lungs was suspected when mycobacterial cultures of the sputum repeatedly yielded Mycobacterium avium. A lung biopsy revealed chronic inflammation without evidence of alveolar capillaritis. A diagnosis of NTM pulmonary disease was further confirmed by tissue culture of the lung biopsy specimens. Antituberculous drugs in combination with clarithromycin were given for the treatment of NTM infection. Pulmonary symptoms promptly responded to the treatments. Furthermore, renal function steadily improved after initiation of anti-NTM therapy. To our knowledge, this is the first report of rapidly progressive glomerulonephritis associated with NTM infection.

Colonoscopy is a useful diagnostic tool for transplant recipients with lower abdominal symptoms

Transplant recipients are at higher risk for infection and malignancy due to therapies aimed at preventing rejection. Early detection and successful treatment of such complications is of pivotal importance for both patient and graft survival. In this study, we evaluated findings of 91 colonoscopies and colonic histopathologic findings in recipients who presented with lower gastrointestinal system complaints between January 1996 and January 2003. The study group included 79 renal and liver transplant patients. The indications for colonoscopy were diarrhea (n = 58), abdominal pain (n = 5), hematochezia (n = 19), unexplained anemia (n = 5), thickening of a colonic segment detected on computerized tomography (n = 2), screening for lymphoma (n = 1), and Kaposi's sarcoma (n = 1). During the procedures, all suspicious lesions were biopsied and specimens of normal-appearing mucosa collected when deemed necessary in relation to the clinical complaints. The endoscopic findings were classified as follows: 0 = "normal," with clear visualization of the vascular network and normal-appearing mucosa; 1 = "erythema", with tissues showing erythema, edema, hyperemia, and loss of normal vascular network; 2 = "ulcerative," with tissues exhibiting ulceration and fragility; and 3 = "coincidental findings," such as polyp or angiodysplasia. Colonoscopic and/or histopathologic abnormalities were detected in 44.5% of the 91 colonoscopy procedures. The results indicate that colonoscopy is a valuable diagnostic tool for evaluation of transplant recipients with lower gastrointestinal complaints. After an initial workup colonoscopy is important to establish an accurate diagnosis.

Gastrointestinal infections in the immunocompromised host

The gastrointestinal tract is a common site of infection in the opportunistic host. Pathogens range from highly virulent organisms, which infect people with well functioning immune systems as well as people with poorly functioning immune systems, to opportunistic organisms, which infect only those with impaired immune systems. Viruses, bacteria, fungi, and protozoa lead to disease that can be especially severe, debilitating, and difficult to treat in the immunocompromised host. Yet in this era of highly active antiretroviral therapy for HIV-infected patients and strategies to reduce immunosuppression in transplant and oncology patients, appropriate diagnostic tests and treatment can both improve the quality of life and decrease mortality. In this article, I review the changing pathogenesis, epidemiology, clinical presentation, diagnosis, and treatment of gastrointestinal infections in the immunocompromised host.

Gastrointestinal infections in the immunocompromised host

Infectious diseases of the gastrointestinal tract continue to be an important source of morbidity and mortality. Viruses, bacteria, fungi, and protozoa that infect normal hosts also infect the gastrointestinal tract in immunocompromised hosts. Disease caused by these pathogens may be more severe and more difficult to treat in immunocompromised hosts. In addition, pathogens that rarely cause disease in normal hosts cause significant disease in immunosuppressed hosts. Diagnostic decisions need to take into account expected pathogens and response to therapy. Treatment decisions must be based on the findings of diagnostic procedures; expected pathogens; and recent data suggesting that highly active antiretroviral therapy, with its ability to reconstitute immune function, is an essential component of treatment. This review summarizes the most important developments made in the pathogenesis, clinical presentation, diagnosis, and treatment of gastrointestinal infections in immunocompromised hosts in the past year.