To the Editor:
Kaposi sarcoma (KS) is an angioproliferative tumor of endothelial origin associated with human herpesvirus 8 infection. It is one of the most prevalent opportunistic infections associated with AIDS and is considered an AIDS-defining illness. In the general population, the incidence of KS is 1 in 100,000 worldwide.1 At the onset of the human immunodeficiency virus (HIV) epidemic in the early 1980s, 25% of individuals with AIDS were found to have KS at the time of AIDS diagnosis. Beginning in the mid-1980s and early 1990s with the introduction of highly active antiretroviral therapy (HAART), the incidence of KS declined to 2% to 4%,2 likely secondary to restoration of immune response.3
The clinical course of KS ranges from benign to severe, involving both cutaneous and visceral forms of disease. Cutaneous KS is the most common form of disease and typically characterizes the initial presentation. It is classically described as violaceous patches, papules, or plaques that can become confluent, forming larger tumors over time. Biopsy of cutaneous lesions may vary based on the clinical morphology. The patch stage typically is characterized by abnormal proliferating vessels surrounding larger ectatic vessels.4 Vascular spaces are more jagged and lined by thin endothelial cells extending into the dermis, forming the classic promontory sign.5 In the plaque stage, the vascular infiltrate becomes more diffuse, involving the dermis and subcutis, and there is proliferation of spindle cells.4 In the nodular stage, spindle-shaped tumor cells form fascicles and vascular spaces become more dilated.4,5 Advanced lesions are further associated with hyaline globules staining positive with periodic acid–Schiff.4 Lymphocytes, plasma cells, and hemosiderin-laden macrophages are admixed within this pathologic architecture.4,5
Visceral KS most commonly occurs in the oropharynx, respiratory tract, and gastrointestinal tract, and rarely is the initial presentation of disease. Classically, visceral KS is an aggressive, potentially life-threatening form of disease and has been found to have a much worse prognosis than cutaneous KS alone. Pulmonary involvement is the second most common site of extracutaneous KS and is known as the most severely life-threatening form of disease.1 Interestingly, since the advent of HAART, the incidence of KS with involvement of the visceral organs has declined at a more dramatic rate than cutaneous KS alone.3 Therefore, although more aggressive in nature, KS with visceral features has become increasingly rare and should be largely preventable given advances in AIDS therapy. We present a case of advanced AIDS-related KS with pulmonary involvement that is rarely seen after the advent of HAART.
A 39-year-old man with HIV diagnosed 8 years prior presented with fever, chest pain, progressive dyspnea, and hemoptysis of 5 months’ duration. At the time, he was nonadherent to medications and had poor follow-up with primary care physicians. At presentation he was tachycardic (149 beats per minute), tachypneic (26 breaths per minute), and his oxygen saturation was 80% on room air. Physical examination of the skin revealed asymptomatic violaceous penile lesions that the patient reported had been present for the last 8 months (Figure 1). Pertinent laboratory values included an HIV-1 viral load of 480,135 copies/mL (reference range, <20 copies/mL) and CD4 count of 14 cells/mm3 (reference range, 480–1700 cells/mm3). A chest radiograph was obtained and revealed bibasilar opacities compatible with a pleural and/or parenchymal process. Bronchoscopy was then performed and revealed bloody secretions throughout the tracheobronchial tree.