Parotid gland lymphoepithelial cysts in HIV infection. (Imaging Clinic).

The development of parotid gland lymphoepithelial cysts in the early stages of human immunodeficiency virus (HIV) infection is considered a precursor to acquired immunodeficiency syndrome (AIDS). (1) It is usually associated with lymphadenopathy, fatigue, night sweats, diarrhea, and weight loss. Associated opportunistic infections or malignant neoplasms might not be present in this early stage. (2)

In the case illustrated here, an 18-year-old man was evaluated for bilateral painless parotid gland swelling of 1 month's duration. He had been previously diagnosed with HIV infection, and his CD4 count was 202 cells/[micro]l.

He was otherwise asymptomatic. Computed tomography (CT) detected bilateral parotid cysts and bilateral lymphadenopathy in the posterior cervical spaces (figure).

The differential diagnosis of parotid gland enlargement in an HIV-positive patient includes reactive lymphadenopathy (follicular hyperplasia), parotid cyst formation, and diffuse infiltration of the gland by lymphoid elements accompanied by cystic dilation of the salivary ducts (diffuse infiltrative lymphocytosis syndrome). (2,3) Sjorgren's syndrome is also a consideration when there is enlargement of the parotid glands, with or without HIV infection. The histologic distinction between AIDS-related parotid lymphoepithelial cysts and the cystic benign lymphoepithelial lesions of Sjorgren's syndrome is that in AIDS, the cysts occur in the parotid lymph nodes, whereas in Sjogren's syndrome, they occur in the parotid parenchyma. (4)

The lymph nodes in the parotid glands are known to contain salivary gland acini and ducts. Since lymphoid tissue is vulnerable to HIV infection, intranodal epithelial proliferation can occur, causing cyst formation. Submandibular gland cysts have also been observed in HIV-positive patients, but this appears to be uncommon. (5)

Parotid gland lymphoepithelial cysts are painless and slow-growing. They can suggest the presence of HIV infection in a patient with cervical lymphadenopathy. These cysts usually involve the superficial parotid lobe bilaterally. Multiple cysts are more common than single cysts. Their size varies from 0.5 to 5 cm in diameter. (4) Clinical symptoms of HIV infection can involve virtually any body system, including the salivary glands. (4) CT, ultrasound, and magnetic resonance imaging are effective in detecting parotid gland cysts and cervical lymphadenopathy.

References

(1.) Mandel L, Reich R. HIV parotid gland lymphoepithelial cysts: Review and case reports. Oral Surg Oral Med Oral Pathol 1992;74:273-8.

(2.) Rosenberg ZS, Joffe SA, Itescu S. Spectrum of salivary gland disease in HIV-infected patients: Characterization with Ga-67 citrate imaging. Radiology 1992;184:761-4.

(3.) Fisehbein NJ, Dillon WP. Imaging of otolaryngologic manifestations of HIV infection. Neuroimaging Clin N Am 1997;7:375-99.

(4.) Som PM, Brandwein MS, Silvers A. Nodal inclusion cysts of the parotid gland and parapharyngeal space: A discussion of lymphoepithelial, AIDS-related parotid, and branchial cysts, cystic Warthin's tumors, and cysts in Sjogren's syndrome. Laryngoscope 1995:105:1122-8.

(5.) Gottesman RI, Som PM, Mester J, Silvers A. Observations on two cases of apparent submandibular gland cysts in HIV positive patients: MR and CT findings. J Comput Assist Tomogr 1996;20:444-7.

From the Department of Radiology, Louisiana State University Health Science Center, New Orleans.