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HIV infection in the human gastrointestinal (GI) tract is thought to be central to HIV progression, but knowledge of this interaction is primarily limited to cohorts within Westernized countries. Here, we present a large cohort recruited from high HIV endemic areas in South Africa and found that people living with HIV (PLWH) presented at a younger age for investigation in the GI clinic. We identified severe CD4+ T cell depletion in the GI tract, which was greater in the small intestine than in the large intestine and not correlated with years on antiretroviral treatment (ART) or plasma viremia. HIV-p24 staining showed persistent viral expression, particularly in the colon, despite full suppression of plasma viremia. Quantification of mucosal antiretroviral (ARV) drugs revealed no differences in drug penetration between the duodenum and colon. Plasma markers of gut barrier breakdown and immune activation were elevated irrespective of HIV, but peripheral T cell activation was inversely correlated with loss of gut CD4+ T cells in PLWH alone. T cell activation is a strong predictor of HIV progression and independent of plasma viral load, implying that the irreversible loss of GI CD4+ T cells is a key event in the HIV pathogenesis of PLWH in South Africa, yet the underlying mechanisms remain unknown.

Khan and colleagues highlight that up to one in six patients with acute symptomatic posterior vitreous detachment have a resultant retinal tear and that dilated funduscopy is needed in all cases.1 Untreated tears can result in retinal detachment and sight loss. It is important to ensure that whoever performs funduscopy is adequately trained and uses the appropriate …

Background: Outer retinal defects (ORDs) may occur after surgical closure of full thickness macular holes (FTMH) and be associated with delayed visual recovery. This may be due to the nature of the subretinal fluid (SRF) cuff and/or the loss of retinal elements. Methods: Vitrectomy with internal limiting membrane (ILM) peel was performed for FTMH. After fluid-air exchange, SRF was either aspirated from the hole (group 1) or left in situ (group 2). The SRF specimens obtained were examined by light microscopy and correlated with optical coherence tomography (OCT). Results: In group 1, cellular material was found in 6 out of 12 cases. Photoreceptors were seen in 3 and macrophages in 3 cases. Nine of 12 holes closed and ORDs were seen in 3 of these. In group 2, 7 out of 8 holes closed, with 4 having ORD. There was no difference in visual acuity (LogMAR) for closed holes at 3 months between groups 1 (0.61, range 0.3–1) and 2 (0.51, range 0.3–0.78) nor between patients with ORD (0.57, range 0.3–1.0) or without ORD (0.57, range 0.3–1.0). Conclusions: SRF from FTMH may contain macrophages and photoreceptors. Such photoreceptor loss may contribute to reduced retinal function. ORDs occur commonly in spite of fluid aspiration, but their presence is still compatible with good vision. Aspiration of SRF did not appear to confer added benefit in this series.

Idiopathic full-thickness macular holes develop as a result of anteroposterior and tangential traction exerted by the posterior vitreous cortex at the fovea. Vitreoretinal relationships during the development of macular holes can be demonstrated in detail by ocular coherence tomography, facilitating an improved understanding of their pathogenesis and guiding clinical management. Surgical strategies for the repair of macular holes are designed to relieve vitreofoveal traction and to promote flattening and reapposition of the macular hole edges by intraocular gas tamponade. A period of face-down positioning postoperatively is conventionally advised. However, the evidence to support this recommendation is weak and practice varies considerably. Surgical removal of the inner limiting membrane (ILM) is advocated to ensure thorough removal of any tangential tractional components including any residual cortical vitreous. Current evidence suggests that ILM peeling can improve anatomical outcomes but the effect on visual function is less predictable; unsuccessful attempts to peel the ILM can be associated with poor visual outcome. The use of vital dyes can facilitate visualisation of the ILM and help achieve complete, atraumatic peeling. Indocyanine green dye can enable high rates of macular hole closure but has been associated with poorer visual outcomes suggesting a dose-dependent toxicity. Trypan blue dye offers an alternative that may have a more favourable risk profile. An improved understanding of vitreoretinal relationships may facilitate a tailored approach to surgery in individuals with macular holes. Vitrectomy to relieve anteroposterior traction is central in the management of all full-thickness holes. The use of long-acting gases, prolonged face-down positioning, and ILM peeling may be more valuable for larger holes, longstanding holes, and those that have failed to close following conventional surgery.