Diffuse infiltrative lymphocytosis syndrome

Diffuse Infiltrative Lymphocytosis Syndrome (DILS) is a rare immunological condition characterized by the persistent infiltration of lymphocytes into various tissues, most notably the salivary glands and lungs. This syndrome is often associated with HIV infection and is considered one of the HIV-associated diseases. DILS shares some clinical features with Sjögren's syndrome, a more common autoimmune disorder affecting similar organs, but DILS is distinct in its etiology and association with HIV.

Etiology

DILS is primarily associated with HIV infection. The exact mechanism by which HIV leads to DILS is not fully understood, but it is thought to involve an abnormal immune response to the virus. In patients with DILS, there is a marked CD8+ lymphocytic infiltration into affected tissues, which differs from the primarily CD4+ lymphocytic infiltration seen in other HIV-related diseases.

Clinical Presentation

Patients with DILS typically present with symptoms related to the organs involved:

• Salivary Glands: Enlargement of the parotid glands, dry mouth, and difficulty swallowing.
• Lungs: Respiratory symptoms such as cough, dyspnea, and occasionally abnormal chest radiographs showing interstitial infiltrates.
• Other Organs: Less commonly, DILS can affect the kidneys, liver, and eyes.

Diagnosis

Diagnosis of DILS involves a combination of clinical evaluation, imaging studies, and laboratory tests:

• HIV Testing: Confirmation of HIV infection is crucial, as DILS is primarily associated with this virus.
• Imaging: Ultrasound or MRI of the salivary glands and chest X-rays or CT scans for lung involvement.
• Biopsy: Histological examination of affected tissues showing lymphocytic infiltration.

Treatment

Treatment of DILS focuses on managing symptoms and controlling the underlying HIV infection:

• Antiretroviral Therapy (ART): Effective control of HIV with ART can lead to improvement of DILS symptoms.
• Corticosteroids: These may be used to reduce inflammation in severely affected tissues.
• Symptomatic Treatment: For example, pilocarpine for dry mouth or supplemental oxygen for respiratory distress.

Prognosis

The prognosis for patients with DILS varies. With effective HIV management, many patients experience stabilization of symptoms and some may see partial regression of glandular swelling and respiratory issues. However, the chronic nature of the disease can lead to complications over time.

Epidemiology

DILS is a rare condition, and its prevalence is not well-documented. It appears more frequently in individuals with poorly controlled HIV infection and is less common in the era of effective antiretroviral therapy.

See Also

• HIV/AIDS
• Autoimmune diseases
• Lymphocytic infiltration