CASE 13796 Published on 11.09.2016

Pneumatosis Intestinalis in HIV and MAC co-infection


Abdominal imaging

Case Type

Clinical Cases


Sin Yee Foo, Peter Garmany, Oliver Cram

Radiology Department,
Queen Elizabeth University Hospital;
1045 Govan Road G51 4TF Glasgow;

41 years, male

Area of Interest Abdomen ; Imaging Technique Digital radiography, CT
Clinical History

Human Immunodeficiency Virus (HIV) patient presented with cachexia, constipation, bloating and abdominal swelling.
CD4+ lymphocyte count was 12 cells/mm3 and plasma viral load was <40 copies/ml while receiving highly active anti-retroviral therapy (HAART) suggesting failure to reconstitute. He was diagnosed with Mycobacterium Avium Complex (MAC) infection five years ago.

Imaging Findings

Presentation abdominal XR to evaluate cause for abdominal distension demonstrated dilated loops of large bowel with evidence of florid intramural gas i.e. pneumatosis intestinalis (Fig 1).
When compared with an earlier abdominal film three months ago, similar but less severe pneumatosis was demonstrated.

Subsequent CT of the abdomen and pelvis demonstrated gross ascites and thickened, collapsed small bowel loops. Findings which are characteristic for MAC infection (Fig. 2). In addition, there is gross pneumatosis of the large bowel wall throughout its entire length. These were more conspicious on lung windows (Fig. 3).


Pneumatosis intestinalis is a rare finding in patients who are HIV-seropositive. Literature search with the keywords ‘HIV’, ‘AIDS’, ‘pneumatosis’ returned only 20 relevant items with the first case of pneumatosis intestinalis reported in an AIDS patient in 1990. [1]

It is defined as the presence of gas within the serosal or mucosal layer bowel wall. [2]
Many authors have theorised that pneumatosis in immunocompromised patients are secondary to bowel infarction or perforation due to infection. [3] But others have also suggested that gas-forming bacteria gain access to the submucosa via breaks and form gas within the bowel wall. [4]

Co-infection with MAC or Cryptosporidium is not uncommon in HIV patients. As in the case of our patient, along with the end-stage intramural pneumatosis, he also displayed radiological findings for MAC infection. He was diagnosed with antibiotic resistant MAC infection 5 years prior to this presentation and had remained on treatment.
No case reports on a patient with MAC and HIV infection who is known to have pneumatosis intestinalis have been published to date on literature review.

Many cases of HIV associated pneumatosis reported were incidental findings and clinical correlation is important. As in this patient, there was no requirement for surgical intervention. The patient was able to eat and drink normally and managed conservatively. Pneumatosis can be difficult to identify on different CT windows and appropriate alteration of CT windowing should be done to improve the sensitivity of detecting this abnormality, especially when it is subtle.

In an acutely unwell patient, for example with intestinal infarction, pneumatosis of this degree would present with greater clinical deterioration and abnormal laboratory findings. However, by comparing it with a three month old radiograph, it appeared that the pneumatosis in this patient was longstanding, similar to existing literature on this topic. And so, no surgical intervention was required.

It remains important to note that an acute surgical abdomen needs to be thoroughly investigated, even in a patient with a history of chronic pneumatosis.

Differential Diagnosis List
Chronic pneumatosis intestinalis as a feature of HIV infection.
Bowel infarction
Chronic pulmonary/airways disease
Final Diagnosis
Chronic pneumatosis intestinalis as a feature of HIV infection.
Case information
DOI: 10.1594/EURORAD/CASE.13796
ISSN: 1563-4086