Among the challenges that complicate optimal health care delivery in rural settings is lack of communication between care providers and patients. Communication of abnormal laboratory results represents a particular challenge. Laboratory and other test results are often not reported until repeat visits weeks to months later. In the case of treatment failure, severe treatment complications, or evidence of opportunistic infection, such reporting delays likely result in adverse outcomes and potentially compromise future treatment options. The investigators propose to evaluate a novel strategy of communication using SMS text messaging to facilitate patient return to an HIV clinic in Uganda after critical laboratory results.