sábado, 22 de agosto de 2015

Holoinspiratory Wheezing in a 46-Year-Old HIV-Seropositive Man - ANSWER

Figure 1. Computed tomographic scan of the chest revealing multiple cavitary pulmonary lesions (A) and tracheal subocclusion (B, arrow). C, Inset shows endoscopic appearance of tracheal subocclusion caused by papillomatous exophytic lesions extending over 4 cartilaginous rings. Air passage was possible only through a small hole (arrow).

Diagnosis: Respiratory papillomatosis of the trachea and lungs due to human papillomavirus infection. 

This patient presented with airway obstruction caused by tracheal papillomatous masses revealed on computed tomography and bronchoscopy (Figure 1). In addition, he had multiple bilateral cavitary lesions in his lungs (Figure 1A). Histological examination of tracheal biopsy samples showed respiratory papillomatosis with low-grade epithelial dysplasia (Figure 2) and koilocytotic atypia (Figure 3B). 
Immunohistochemical analysis for human papillomavirus (HPV) performed with antiHPV L1 (Cytoactiv Diagnostics GmBH, Pirmasens, Germany) showed positive nuclear staining of the koilocytes (Figure 3C). Even though lung nodules were not biopsied, other possible causes were ruled out in the bronchoalveolar lavage, including mycobacteria, bacterial organisms, and fungi. The patient was treated by rigid bronchoscopy with YAG (yttrium neodymium) laser therapy to relieve the tracheal obstruction, resulting in normalization of his arterial blood gas and amelioration of his respiratory symptoms. However, he experienced recurrence of the tracheal lesions and died of unrelated causes 20 months after the diagnosis. Recurrent respiratory papillomatosis (RRP) is a rare cause of benign tumors of the respiratory tract caused by HPV. Most commonly it involves the larynx and trachea, but rarely can spread distally to affect the bronchi and lung parenchyma. Although benign, it carries significant morbidity and occasional mortality, including life-threatening airway obstruction and a 3%–5% risk of malignant transformation. Pulmonary involvement heralds a poor prognosis and manifests in 1.8% of RRP patients, predominantly children, with multiple nodules and thin-walled cysts apparent on computed tomography. RRP has a bimodal age distribution: Juvenile-onset disease is thought to result from vertical transmission at the time of delivery, or, in some cases, from infection in utero; adult-onset disease may result from sexual or oral transmission. Its incidence in the United States has been estimated at 4.3/100 000 per year in children and 1.8/100 000 per year in adults. HPV is a nonenveloped double-stranded DNA virus, which replicates inside the nuclei of infected epithelial cells and is able to persist in basal cells as an episome. More than 100 types of HPV are known, but the majority of RRP is secondary to the low-risk types 6 and 11, with the latter being more virulent. Both the humoral and the cellular immune response may be compromised in patients with respiratory papillomatosis, and the patient’s degree of immunodeficiency may be associated with the clinical course of the disease. In particular, a compromised cell-mediated immune response has been associated with the development of RRP in children. In contrast to the link between HPV-mediated cervical and anogenital cancers with HIV infection, there is no known association of HIV with RRP. The condition is incurable. The mainstay of treatment is surgical debulking, predominantly through laser therapy or use of microdebriders. Multiple procedures may be necessary due to frequent, repeated recurrences. Various adjuvant treatments have been tried, including antivirals (mainly intralesional cidofovir) and immunomodulators (eg, interferon alfa), but highquality evidence to support their use is lacking. The advent of a quadrivalent HPV vaccine targeting types 6, 11, 16, and 18 is a promising development that could lead to prevention or even eradication of this condition in the long term.

Figure 2. Hematoxylin-eosin stain of tracheal biopsy material (×200 magnification).

Figure 3. A, Histopathological features of respiratory papillomatosis (hematoxylin-eosin stain, ×200 magnification). B, Arrows indicate the koilocytotic cells that show an intense immunoreaction for human papillomavirus (C, arrows). The koilocytes show well-defined perinuclear halos with a cookie-cutter border and cytoplasmic thickening; nuclei are enlarged (sometimes bi- or multinucleated with variation in nuclear size) with undulating (raisin-like) nuclear membrane.

Clinical Infectious Diseases 2014;58(1):134–5
DOI: 10.1093/cid/cit666

0 comentarios:

Dí lo que piensas...