Human immunodeficiency virus (HIV) transmission remains an important health problem, with an impactful burden across the world. In 2020, 14971 cases of HIV were diagnosed in Europe.1 The last available report on HIV diagnosis in Portugal reported 778 new cases back in 2019, 50% of the patients presenting with a CD4+ count<350cells/mm3 (late presenters).2

Dermatologists play an important role in HIV diagnosis, as in many European countries such as Portugal, dermatologists are responsible for providing both dermatological and sexually transmitted infections (STI) care. In Italy, Mandel et al. found a yearly rate of HIV positive tests ranging from 0.1% to 1% in patients attending a Sexually Transmitted Diseases Ambulatory Dermatology Unit without a previous diagnosis.3 A similar work also conducted in Portugal by Mendes-Bastos et al. found a positivity rate of 3% in HIV of the patients who attended a Dermatology unit.4

The most common concomitant diagnosis made in newly diagnosed HIV patients in Dermatology units is syphilis, with an incidence rate ranging from 19% to 39%.4,5 Most newly diagnosed cases of HIV in this setting have a concomitant STI diagnosis (52–61%).4,5 Besides STI, other dermatological conditions previously described associated with HIV diagnosis include prurigo nodularis, psoriasis, shingles, and Kaposi sarcoma.4,5

This work aims to characterize the demographic, clinical, and laboratory characteristics of patients with newly diagnosed HIV infections in the Department of Dermatology and Venereology of a Portuguese hospital.

HIV diagnosis continues to be a challenging subject amongst health care providers. Dermatology and Venereology Departments are responsible for providing health counseling on STIs, thus having a privileged position to take action on HIV diagnosis. As far as we know, this is the largest published database on newly diagnosed patients with HIV in a dermatological setting.

Our study has important limitations. First, there is a selection bias; patients attending our unit are prone to having more serious, or atypical conditions that require a specialized assessment in a tertiary care center such as ours. Secondly, there is information bias since all data was gathered through previously recorded medical data, with a significant percentage of missing data.

A total of 134 patients were diagnosed in the 10-year period of this study, with a mean no. of diagnoses per year of 13.4, a slightly higher rate compared to previous results.3–5 The high rate of diagnoses could be explained by the unique characteristics of our Department, with an available walk-in Dermatology Urgent Care Clinic available on a daily basis, also corroborated by the elevated rate of cases diagnosed in this clinic (67.9%).

Most HIV diagnoses were matched with a dermatological or venereological diagnosis. Regarding the cases without a diagnosis, the positive HIV testing resulted from STI screening in asymptomatic patients, mostly latent syphilis. The most common associated conditions were infectious, with STI accounting for most diagnoses. STIs cause mucosal inflammation, or ulcers in the oral and anogenital areas and increase the risk of HIV transmission.6 In our study, 41.0% of the patients tested positive for a STI, which is similar to what former studies have reported,4,5 with syphilis, gonorrhea, and chlamydia accounting for most of the cases (96.4% of the patients with a laboratory diagnosis of STI). Syphilis showed an extraordinarily high prevalence, with 1 out of 3 patients newly diagnosed with HIV also testing positive for syphilis (33.6%, n=45). Our results once again reinstate that the syphilis epidemic is still a matter of great interest, with the need for policies on screening, treatment, and prevention.7

Our results showed that several dermatoses usually not associated with HIV diagnosis could be found, once again stating the importance of HIV screening programs among health institutions as an approach to increasing diagnosis.1 Regarding dermatosis – excluding STIs – Kaposi sarcoma, psoriasis, and shingles were some of the most common conditions associated with a diagnosis of HIV, a result similar to previously published data.4,5

Of all the patients with recorded CD4 cell count, most were LP (54.5%), and 35.2% presented with AIDS-defining cell counts. Patients presenting with an STI had significantly higher CD4 counts (392cells/mm3) compared to patients with a negative STI testing (133cells/mm3). We hypothesize that patients with a STI are commonly more symptomatic and seek medical help earlier compared to other dermatoses, resulting in a higher CD4 cell count at diagnosis.

HIV and particularly LP are still a major health concern across Europe, where 48% of newly diagnosed HIV patients are LP.8 In Portugal, the rates of patients with newly diagnosed HIV presenting with AIDS ranged from 14.0% to 21.4% from 2010 to 2019, a lower prevalence than that of our study.2

Patients who present as EP to health care providers with good linkage to care can initiate antiretroviral therapy earlier, resulting in viral suppression, decreased rates of co-morbidities, and prevention of future opportunistic infection acquisitions. Therefore, this database on HIV diagnosis associated with dermatosis is crucial to establish plans and recommendations on testing, improving early diagnosis, and reducing morbidity and onward transmission.

The authors declare that they have no conflict of interest.