The role of human immunodeficiency virus in the pathogenesis of vernal keratoconjunctivitis-like disease in adults: A demographic and epidemiological study

Diagnostic criteria of chronic conjunctivitis: atopic keratoconjunctivitis and vernal keratoconjunctivitis

PURPOSE OF REVIEW

Chronic ocular allergies, vernal (VKC) and atopic keratoconjunctivitis (AKC) are relatively rare conditions that require definite diagnostic criteria to the most appropriate therapeutical approach.

RECENT FINDINGS

The diagnosis of both VKC and AKC is generally based on clinical history, signs and symptoms, and the results of allergic tests, which allow to identify the different diseases phenotypes. However, other subtypes of the two diseases and/or overlaps may occur making the diagnosis non always so clear, such as VKC and AKC overlaps or adult-like VKC disease. Each of these phenotypes may be sustained by different mechanisms which are still not well defined but not only related to a type 2 inflammation. The further challenges will be to correlate clinical or molecular biomarkers to a single subtype or disease severity.

SUMMARY

Definite criteria of chronic allergies will further guide to more specific therapeutical approaches.

Prevalence and clinical characteristics of vernal keratoconjunctivitis in sub-Saharan Africa

PURPOSE OF REVIEW

Vernal keratoconjunctivitis (VKC) is a chronic bilateral allergic inflammatory disease of the conjunctiva and cornea that affects children and young adults, especially in sub-Saharan Africa. A limbal form (tropical endemic limbo conjunctivitis) is thought to be more common in the tropics where research on this vision-impairing condition is scanty. We sought to review current literature from sub-Saharan Africa, with a focus on the prevalence of VKC and its clinical presentation.

RECENT FINDINGS

There is a variable prevalence of VKC in SSA, up to 32.9% of children, especially in male individuals less than 5 years old, and has been diagnosed in a 4-month-old baby. Associated factors include exposure to dust, personal and family history of atopy, Vitamin D3 deficiency and HIV. The mixed form of VKC is the most frequent form seen and conjunctival pigmentation might be an early diagnostic sign.

SUMMARY

Childhood screening programs for VKC should be established to reduce the morbidity, decreased quality of life and school absenteeism that is seen in these patients. VKC-related research should be encouraged in this milieu to bring to light the particularities of VKC in SSA.

The multifaceted aspects of ocular allergies: Phenotypes and endotypes

Like the lung, skin, and nose, the external eye is a common target of allergic inflammation. Ocular allergy (OA) represents a collection of underestimated diseases of the eye observed in children and adults. The ocular manifestations are the expression of multifactorial immune mechanisms that generally have a good prognosis, but for a few patients, long term inflammation may remarkably reduce the visual function. Evidence suggests that other co-participant systems, including epigenetic, genetic, environmental, individual factors, sex hormones, and the central and autonomic nervous systems may influence the ocular response from distant sites. This is consistent with the concept that the eye is an organ fully integrated with the rest of the body and that the therapeutic approach should be holistic, dynamic, and personalized. For instance, androgens and estrogens binding to receptors on the ocular surface and the continuous cross-talking of neuromediators and growth factors with immune cells act to maintain the ocular surface homeostasis in response to environmental challenges. The immune system links and regulates the response of the ocular surface. Complex and incompletely understood mechanisms influence the innate and adaptive immune responses and generate different OA phenotypes and endotypes discussed in the present review.