Sicca

Sicca is a Latin term meaning dry. In medical language, sicca is used to describe dryness of mucous membranes and exocrine glands. The most common forms are keratoconjunctivitis sicca, or dry eye, and xerostomia, or dry mouth. When dryness affects multiple mucosal surfaces, the condition is referred to as sicca syndrome.

Sicca syndrome frequently occurs in Sjögren's syndrome, an autoimmune disease. It can be primary, arising without another connective tissue disease, or secondary, associated with conditions such as rheumatoid arthritis or lupus. While Sjögren's is the prototypic cause of sicca symptoms, dryness can also occur in other contexts or as an isolated phenomenon.

Diagnosis involves a combination of history and objective testing. Ophthalmic evaluation includes the Schirmer test to measure tear production, tear film breakup time, and ocular surface staining. Salivary involvement is assessed by measurement of saliva flow (sialometry) and oral examination. Serologic testing for autoimmune markers such as ANA, anti-SSA/Ro, and anti-SSB/La can support a diagnosis of Sjögren's syndrome, and a minor salivary gland biopsy showing focal lymphocytic sialadenitis can confirm glandular involvement.

Management is typically symptomatic and disease-modifying when an underlying autoimmune condition is present. Ocular dryness is treated with artificial tears, lubricating ointments, topical anti-inflammatory drops such as cyclosporine, and sometimes punctal occlusion to conserve tears. Dry mouth is managed with saliva substitutes, good hydration, sugar-free gum, and, in some cases, systemic muscarinic agonists such as pilocarpine or cevimeline to stimulate saliva. Treating the underlying autoimmune disease is important in many patients.

Sicca conditions most commonly affect middle-aged and older adults, with female predominance in autoimmune-associated cases. The prognosis varies with the underlying disease and symptom burden.