Atopic Dermatitis in Latin America: Considerations on Epidemiology, Clinical and Laboratory Features, Ethnic/Racial Variations, and Therapeutic Management

Abstract

Latin America (LA) encompasses about 8.5% of the world’s population, exhibits ethnic/racial heterogeneity and social inequality. We hereby present a 20-year literature review (2004–2023) on epidemiology, diagnosis, clinical and laboratory features, quality of life and management of atopic dermatitis (AD) in LA. Highest AD prevalence for children aged 6–7 years was reported in Ecuador (22.5%) and Colombia (20.9%), for adolescents in Colombia (24.6%) and for all ages, in Brazil (20.1%). Regions with a predominantly Black population in LA varied significantly, ranging from 4.4% in Northern Brazil to 10.1% in Cuba, indicating genetic variation among African subgroups. Filaggrin loss-of-function mutations showed variants seen in Europeans in 9.3% of Chilean patients and studies in Brazil revealed impaired expression of filaggrin and claudin-1 in the skin but increased expression in conjunctival epithelia of AD patients. The most reported AD features included erythema, pruritus, and dry skin, with marked lichenification. Severe pruritus was reported by 54.4% of patients and a high impact on quality of life was detected in 50% of adults with AD. In Brazilian referral hospitals, 65.6% of patients were classified as having severe AD, and 56% had one or more hospitalizations during their lifetime, indicating a need for better disease control. Diagnosing AD is challenging due to broad clinical features, ethnoracial variations and lack of universal diagnostic criteria. Furthermore, lack of physician training, barriers to medication access, and socioeconomic inequalities hinder effective disease management in LA.

Ethnic and Racial Disparities in Clinical Manifestations of Atopic Dermatitis

“…Patients with AD were found to have erythema (54.5%), pruritus (55.1%), and dry skin (48.7%) at their initial assessment [ 63 ]. The lesions displayed the classic lichenified or eczematous morphology [ 64 ]. Among 1,650 Argentinians with AD, 40% exhibited substantial itching in terms of intensity and frequency [ 65 ].…”

“…Several studies have been conducted to investigate the association between the prevalence of AD and variations in disease severity among individuals of different racial backgrounds. These studies have examined differences in the composition of stratum corneum ceramides, transepithelial water loss (TEWL) [ 114 ], pH levels [ 115 ], mutations in the filaggrin gene [ 64 ], and the presence of Staphylococcus aureus in the nasal passages. None of these factors in isolation can be solely attributed to the different presentation of Atopic Dermatitis in African American (AA) versus European American individuals.…”