Classic kaposi sarcoma with pulmonary involvement mimicking endobronchial tuberculosis in a child

Rapidly progressive Kaposi's Sarcoma in an Iraqi boy received Valproic acid: a case report and review of literature

Background

Kaposi’s sarcoma (KS), an endothelial neoplasm, is associated with human herpes virus (HHV) -8 infection. KS has four clinical sub-types: Mediterranean/classic, African/endemic, human immunodeficiency virus (HIV) -associated/epidemic, and transplantation-related/iatrogenic. Immunosuppression is an important cofactor in KS process. Classic KS (CKS) is exceedingly rare in children and when occurs, it is much more disseminated than adults. The epidemic, HIV-associated and the iatrogenic forms of childhood KS are a result of a profound and acquired T-cell deficiency. To our knowledge, this is the first paediatric KS case report from Iraq. Our patient was showing an unusual aggressive course of the disease while receiving Valproic acid (VPA) of the potential immune-suppressive effect.

Case presentation

A six-year-old Iraqi boy, who had cerebral palsy (CP) and epilepsy since the age of 9-months, had received VPA to control his seizures. He developed skin discoloration followed by nodules that disseminated proximally from the lower extremities to the groin, face, ears and oral cavity, and then he died from severe respiratory distress after 110 days from the disease evolution. KS diagnosis was proved by a skin biopsy. As the patient was of Arab-Asian ethnicity and was HIV-seronegative status, accordingly, his condition best fitted the classic form of KS. However, recent studies showed the link of VPA with the reactivation of HHV-8. Moreover, accumulated experimental and clinical data elucidated that VPA induces T-cell suppression. Given that there was a lack of facilities to perform the laboratory immunological diagnostic tests in Iraq, the VPA-induced effect on immunity in our case (iatrogenic KS) could not be evaluated.

Conclusions

Our report demonstrates a rare, rapidly progressing paediatric KS case and highlights the possible role of the 5-years’ administration of VPA and its challenging effect on cellular immunity based on recent studies. Thus, VPA could have promoted the development of the KS in our patient. This report also recalls the need of paediatricians to consider KS especially when the skin lesion appears at the child’s foot even in countries outside the geographical map of the disease.

Electronic supplementary material

The online version of this article (doi:10.1186/s12887-016-0653-3) contains supplementary material, which is available to authorized users.

Kaposi Sarcoma of Childhood: Inborn or Acquired Immunodeficiency to Oncogenic HHV-8

Kaposi sarcoma (KS) is an endothelial malignancy caused by human herpes virus-8 (HHV-8) infection. The epidemic and iatrogenic forms of childhood KS result from a profound and acquired T cell deficiency. Recent studies have shown that classic KS of childhood can result from rare single-gene inborn errors of immunity, with mutations in WAS, IFNGR1, STIM1, and TNFRSF4. The pathogenesis of the endemic form of childhood KS has remained elusive. We review childhood KS pathogenesis and its relationship to inherited and acquired immunodeficiency to oncogenic HHV-8.

Case Report: Pulmonary Kaposi Sarcoma in a non-HIV patient

Kaposi Sarcoma (KS) is an angioproliferative tumor associated with human herpes virus 8 (HHV-8).  Often known as one of the acquired immunodeficiency syndrome (AIDS)-defining skin diseases, pulmonary involvement in KS has only been discussed in a handful of case reports, rarely in a non-HIV patient. Herein we report the case of a 77 year-old- male who presented with a 6-week history of progressive dyspnea on exertion accompanied by productive cough of yellow sputum and intermittent hemoptysis. His past medical history was significant for Non-Hodgkin's Follicular B-Cell Lymphoma (NHL). Patient also had biopsy-confirmed cutaneous KS. His physical exam was notable for a 2cm firm, non-tender, mobile right submandibular lymph node.  Lungs were clear to auscultation. He had multiple violet non-tender skin lesions localized to the lower extremities. CT scan of the chest showed numerous nodular opacities and small pleural effusions in both lungs. A thoracenthesis was performed, showing sero-sanguineous exudative effusions. Histopathology failed to demonstrate malignant cells or lymphoma. A subsequent bronchoscopy revealed diffusely hyperemic, swollen mucosa of the lower airways with mucopurulent secretions. Bronchoalveolar lavage PCR for HHV-8 showed 5800 DNA copies/mL.  It was believed that his pulmonary symptoms were likely due to disseminated KS.  This case illustrates the potential for significant lung injury from KS. It also demonstrates the use of PCR for HHV-8 to diagnose KS in a bronchoalveolar lavage sample in a case when bronchoscopic biopsy was not safe. Furthermore, this case is unique in that the patient did not match the typical KS subgroups as HIV infection and other immune disorders were ruled out. Recognition of this syndrome is critical to the institution of appropriate therapy. As such, this case should be of interest to a broad readership across internal medicine including the specialties of Pulmonology and Critical Care.

Inherited human OX40 deficiency underlying classic Kaposi sarcoma of childhood

Human OX40 is necessary for robust CD4⁺ T cell memory and confers selective protective immunity against HHV-8 infection in endothelial cells.

Kaposi sarcoma (KS), a human herpes virus 8 (HHV-8; also called KSHV)–induced endothelial tumor, develops only in a small fraction of individuals infected with HHV-8. We hypothesized that inborn errors of immunity to HHV-8 might underlie the exceedingly rare development of classic KS in childhood. We report here autosomal recessive OX40 deficiency in an otherwise healthy adult with childhood-onset classic KS. OX40 is a co-stimulatory receptor expressed on activated T cells. Its ligand, OX40L, is expressed on various cell types, including endothelial cells. We found OX40L was abundantly expressed in KS lesions. The mutant OX40 protein was poorly expressed on the cell surface and failed to bind OX40L, resulting in complete functional OX40 deficiency. The patient had a low proportion of effector memory CD4⁺ T cells in the peripheral blood, consistent with impaired CD4⁺ T cell responses to recall antigens in vitro. The proportion of effector memory CD8⁺ T cells was less diminished. The proportion of circulating memory B cells was low, but the antibody response in vivo was intact, including the response to a vaccine boost. Together, these findings suggest that human OX40 is necessary for robust CD4⁺ T cell memory and confers apparently selective protective immunity against HHV-8 infection in endothelial cells.