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Assessing the Innate Sensing of HIV-1 Infected CD4+ T Cells by Plasmacytoid Dendritic Cells Using an Ex vivo Co-culture System.
Published on: September 1, 2015
[Idiopathic CD4+ T-lymphocytopenia in 2 patients without indications for HIV infection]
W Pohl1, C Armbruster, K Bernhardt
1Medizinische Abteilung, Pulmologisches Zentrum der Stadt Wien.
Insights
Idiopathic CD4+ T cell depletion, a condition distinct from HIV, presents unique immunological profiles and a better prognosis. This rare disorder shows potential for CD4+ T cell count recovery over time.
Area of Science:
- Immunology
- Virology
- Pulmonology
Background:
- Idiopathic CD4+ T cell depletion is a rare condition characterized by a significant decrease in CD4+ T lymphocytes without an identifiable cause.
- Distinguishing it from HIV infection is crucial for appropriate patient management and prognosis.
Observation:
- Two patients presented with idiopathic CD4+ T cell depletion: one with acute respiratory failure and bronchiolitis obliterans organizing pneumonia (BOOP), the other with mucocutaneous fungal infection.
- Both patients tested negative for HIV types 1 and 2 through comprehensive serological, antigen, PCR, and viral culture methods.
Findings:
- The first patient's respiratory symptoms improved with high-dose corticosteroid therapy, despite initial antibiotic treatment failure.
- The second patient's CD4+ T cell depletion was transient and resolved with antifungal treatment.
- Both patients exhibited distinct immunological profiles compared to HIV-infected individuals, with a tendency towards CD4+ T cell count normalization over time.
Implications:
- Idiopathic CD4+ T cell depletion represents a distinct clinical entity from HIV infection, characterized by a different immunological profile and a more favorable prognosis.
- Further research is needed to determine if this is a novel syndrome and to elucidate its potential causes, such as transmissible agents or genetic predispositions.
Abstract:
We report on two patients with idiopathic CD4+ T cell depletion. A 26 year-old woman presented to us with acute respiratory failure requiring mechanical ventilation. Despite combined antibiotic therapy parenterally the opacities increased in the chest X-ray. An open lung biopsy was performed and led to the histological diagnosis of bronchiolitis obliterans organizing pneumonia (BOOP). Respiratory function was improved impressively by high dose parenteral cortisone administration. This patient showed a general lymphocytopenia with severe CD4+ T cell depletion (60(37%)/mm3 blood). The CT4+ T cell concentration increased during a follow up period of 14 months, but did not reach normal values. The second patient was a 33 year-old homosexual. He was admitted with a mucocutaneous fungal infection which was successfully treated by antifungal drugs. This patient demonstrated a transient CD4+ T cell depletion (350(32%)/mm3 blood). In both patients HIV type 1 and 2 infections were excluded by antibody- and p 24-antigen testing, polymerase chain reaction and virus culture. CONCLUSION. Idiopathic CD4+ T lymphocytopenia differs from HIV infection in immunological profile, in the tendency to reversal of the CD4+ T cell depletion over time and in its better prognosis. It is unclear if this is a new syndrome and whether a transmissible agent, or possibly a genetically-determined reaction to noxious agents is responsible.
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