Kager's fat pad inflammation associated with HIV infection and AIDS: MRI findings

Skeletal Radiol. 2014 Sep;43(9):1257-62. doi: 10.1007/s00256-014-1931-5. Epub 2014 Jun 12.


Objective: To describe magnetic resonance imaging (MRI) features of Kager's fat pad inflammation in HIV-positive patients with lipodystrophy due to protease inhibitor treatment and posterior ankle pain.

Methods: A case-control, cross-sectional study; group 1 included 14 HIV-positive patients using protease inhibitors, presenting lipodystrophy syndrome and having posterior ankle pain; group 2 (CGHIV-) included 112 HIV-negative patients without lipodystrophy syndrome who were being evaluated for posterior ankle pain; group 3 (CGHIV + 1) included 23 HIV-positive patients not using a protease inhibitor, without lipodystrophy syndrome and with posterior ankle pain; group 4 (CGHIV + 2) comprised 18 HIV-positive patients who were being treated with a protease inhibitor and had lipodystrophy syndrome but did not have posterior ankle pain. Images were evaluated for the presence of edema by two radiologists who were blinded to clinical features. Fisher's exact test was used to evaluate differences among the groups. Interobserver variation was tested using Cohen's kappa (κ) statistic.

Results: The presence of edema within Kager's fat pad was strongly associated with symptoms in HIV-positive patients who had lipodystrophy (p ≤ 0.0001). Concordance between observers was excellent (κ > 0.9).

Conclusion: MRI findings of Kager's fat pad inflammation related to HIV/AIDS is a source of symptoms in HIV patients with posterior ankle pain using protease inhibitors and having lipodystrophy syndrome.

Publication types

  • Controlled Clinical Trial

MeSH terms

  • Adipose Tissue / pathology*
  • Adult
  • Ankle Joint / pathology
  • Brazil / epidemiology
  • Case-Control Studies
  • Comorbidity
  • Female
  • HIV-Associated Lipodystrophy Syndrome / chemically induced*
  • HIV-Associated Lipodystrophy Syndrome / epidemiology
  • HIV-Associated Lipodystrophy Syndrome / pathology*
  • Humans
  • Magnetic Resonance Imaging / statistics & numerical data*
  • Male
  • Middle Aged
  • Panniculitis / chemically induced*
  • Panniculitis / pathology*
  • Prevalence
  • Protease Inhibitors / adverse effects*
  • Reproducibility of Results
  • Risk Factors
  • Sensitivity and Specificity


  • Protease Inhibitors