Changes in the incidence of severe thrombocytopenia and its predisposing conditions in HIV-infected patients since the introduction of highly active antiretroviral therapy

Investigating the Role of Anti-TPO Antibodies in HIV-Associated Thrombocytopenia before and after Initiation of HAART: A Case-Control Longitudinal Study

This longitudinal, case-control study aimed to investigate the role of thrombopoietin (TPO) and anti-TPO antibodies in HIV-associated thrombocytopenia, focusing on the changes seen before and after the initiation of highly active antiretroviral therapy (HAART). Patients were assessed before and at least six months after the initiation of HAART. In total, 75 PLWHIV (age/sex-matched and randomized at 2:1, according to thrombocytopenia status) were included in this study. The baseline assessment revealed significantly higher TPO levels in thrombocytopenic patients (140.45 vs. 106.8 mg/mL, p = 0.008). Furthermore, anti-TPO-positive patients displayed lower platelet counts (109,000 vs. 139,000/L, p = 0.002) and TPO levels (114.7 vs. 142.7 mg/mL, p = 0.047). Longitudinally, HAART initiation reduced the frequency of thrombocytopenia from 75.47% to 33.96% (p < 0.001) and elevated the median platelet counts from 131,000 to 199,000 (p < 0.001). No significant difference in median platelet counts was found post-HAART among the anti-TPO subgroups (p = 0.338), a result contrasting with pre-HAART findings (p = 0.043). Changes in anti-TPO status corresponded with significant platelet count alterations (p = 0.036). Notably, patients who became anti-TPO negative showed a median increase of 95,000 platelets (IQR: 43,750-199,500). These marked differences between subgroups underscore the potential role of anti-TPO antibodies in modulating the hematological response to HAART. Further research is needed to elucidate the complex interplay between HIV infection, HAART, and thrombocytopenia.

Challenges in Platelet Functions in HIV/AIDS Management

The interest in platelet functions in HIV/AIDS is due to the high incidence of microvascular thrombosis in these individuals. A lot of laboratory data have been generated regarding platelet functions in this population. The tests demonstrate platelet hyperactivity but decreased aggregation, though results are inconsistent depending on the study design. Antiretroviral treatments currently in use display complex interactions. Many studies on platelet functions in these patients have been for research purposes, but none have found utility in guiding drug treatment of thrombosis.

The global prevalence of thrombocytopenia among HIV-infected adults: A systematic review and meta-analysis

BACKGROUND

Thrombocytopenia is the second most frequent complication of human immunodeficiency virus (HIV) infection, occurring in about 4-40% of HIV-infected patients. This study aimed to determine the global prevalence of thrombocytopenia among HIV/AIDS adults and its association with highly active antiretroviral therapy (HAART).

METHOD

This systematic review and meta-analysis was performed based on Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) guidelines. The Joana Brigg's Institute (JBI) critical appraisal checklist was used for quality appraisal of the included articles. A random-effect model was fitted to calculate the pooled estimates using STATA version-11. A sub-group analysis and sensitivity analysis were carried out to determine the potential source of heterogeneity.

RESULT

Of the 1823 articles that were retrieved, 20 full-text articles were eligible for meta-analysis. The overall pooled prevalence of thrombocytopenia among HIV-infected adults was 17.9% (95% CI: 14.69, 21.12) I² = 96.4%. The pooled prevalence of thrombocytopenia was 21.00% (95% CI: 17.35, 24.65) and 11.64% (95% CI: 6.66, 16.62), before and after initiation of HAART, respectively.

CONCLUSION

Thrombocytopenia is a common comorbidity in HIV patients and HAART was significantly associated with reduced thrombocytopenia. Therefore, prompt start of HAART might help to decrease the prevalence of thrombocytopenia and its subsequent complications.

Autoimmune diseases and HIV infection: A cross-sectional study

To describe the clinical manifestations, treatments, prognosis, and prevalence of autoimmune diseases (ADs) in human immunodeficiency virus (HIV)-infected patients.All HIV-infected patients managed in the Infectious Diseases Department of the Lyon University Hospitals, France, between January 2003 and December 2013 and presenting an AD were retrospectively included.Thirty-six ADs were found among 5186 HIV-infected patients which represents a prevalence of 0.69% including immune thrombocytopenic purpura (n = 15), inflammatory myositis (IM) (n = 4), sarcoidosis (n = 4), Guillain-Barré syndrome (GBS) (n = 4), myasthenia gravis (n = 2), Graves' disease (n = 2), and 1 case of each following conditions: systemic lupus erythematosus, rheumatoid arthritis, autoimmune hepatitis, Hashimoto thyroiditis and autoimmune hemolytic anemia. One patient presented 2 ADs. Thirty patients were known to be HIV-infected when they developed an AD. The AD preceded HIV infection in 2 patients. GBS and HIV infection were diagnosed simultaneously in 3 cases. At AD diagnosis, CD4 T lymphocytes count were higher than 350/mm in 63% of patients, between 200 and 350/mm in 19% and less than 200/mm in 19%. Twenty patients benefited from immunosuppressant treatments, with a good tolerance.ADs during HIV infection are uncommon in this large French cohort. Immune thrombocytopenic purpura, sarcoidosis, IM, and GBS appear to be more frequent than in the general population. Immunosuppressant treatments seem to be effective and well tolerated.

Impact of the highly active antiretroviral therapy era on the epidemiology of primary HIV-associated thrombocytopenia

BACKGROUND

Primary HIV-associated thrombocytopenia (PHAT) typically improves with highly active antiretroviral therapy (HAART); however, cases continue to occur. Data comparing the epidemiology of PHAT between the pre-HAART and HAART eras are limited. We retrospectively examined the incidence of PHAT over 28 years in the US Military HIV Natural History Study (NHS) from 1986 to 2013.

RESULTS

Subjects had a nadir platelet count <100 × 10(9)/l with no other identifiable cause. Time periods were categorized as pre-HAART (1986-1995), early HAART (1996-2001), and later HAART (2002-2013). Incidence, demographic data, and CD4 count were compared across the three eras. A generalized estimating equations model was used to assess any association of platelet count and HIV viral load in cases diagnosed during the HAART eras. 218 participants met the case definition. 86.2 % of cases occurred prior to 2002. The incidence of PHAT per 1000 person-years of follow-up was 16.3, 4.6, and 1.9 during pre-HAART, early HAART and later HAART eras respectively. CD4 cell counts were significantly higher in the HAART eras at the time of thrombocytopenia (p < 0.001). Of patients diagnosed after 1996, 96.4 % were viremic within six months preceding the platelet nadir and over half were antiretroviral naïve. Viral load (per log10 copies/ml) inversely correlated with platelet count throughout the HAART eras (p < 0.0001).

CONCLUSIONS

The incidence of PHAT has markedly decreased in the HAART era. However, viremic individuals, including those with healthy CD4 cell counts, may be at risk. Achieving viral suppression as early as possible may decrease the incidence further.

Human platelets and their capacity of binding viruses: meaning and challenges?

Blood platelets are first aimed at ensuring primary hemostasis. Beyond this role, they have been acknowledged as having functions in the maintenance of the vascular arborescence and, more recently, as being also innate immune cells, devoted notably to the detection of danger signals, of which infectious ones. Platelets express pathogen recognition receptors that can sense bacterial and viral moieties. Besides, several molecules that bind epithelial or sub-endothelial molecules and, so forth, are involved in hemostasis, happen to be able to ligate viral determinants, making platelets capable of either binding viruses or even to be infected by some of them. Further, as platelets express both Fc-receptors for Ig and complement receptors, they also bind occasionally virus-Ig or virus-Ig-complement immune complexes. Interplays of viruses with platelets are very complex and viral infections often interfere with platelet number and functions. Through a few instances of viral infections, the present review aims at presenting some of the most important interactions from pathophysiological and clinical points of view, which are observed between human viruses and platelets.