Sjögren’s syndrome (SS) is a chronic autoimmune disorder where the immune system mistakenly targets and damages the body’s moisture-producing glands, primarily the salivary and lacrimal glands. This immune attack leads to decreased function, resulting in dryness. While the most recognized symptom is dry mouth, known medically as xerostomia, it is possible to receive a diagnosis of SS even without experiencing this specific symptom. Sjögren’s is a systemic disease, meaning it can affect various organs and tissues throughout the body, sometimes long before or entirely without the classic sensation of dryness.
The Defining Role of Sicca Symptoms
Sjögren’s syndrome is classically defined by the presence of the sicca complex, which refers to persistent dryness of the eyes and mouth. Dry mouth (xerostomia) results from chronic inflammation and destruction within the salivary glands due to an infiltration of lymphocytes. This lack of saliva can manifest as difficulty swallowing dry foods, needing to sip water frequently, and a heightened risk for dental decay and oral infections. The other half of the sicca complex is dry eyes (keratoconjunctivitis sicca), which occurs when the lacrimal glands are similarly inflamed. Patients often report a gritty or sandy sensation in the eyes, along with redness and a feeling of foreign bodies.
Atypical Presentation: Sjogren’s Without Xerostomia
Although most individuals with SS present with some degree of dryness, an estimated 10% to 20% of patients may not report significant dry mouth or dry eyes, especially early in the disease course. This scenario is often referred to as an “atypical” or “non-sicca dominant” presentation. The disease is systemic from the onset, and its effects on other organ systems can appear years before glandular symptoms become noticeable. Diagnosis in these cases relies on objective evidence of the autoimmune process rather than subjective symptoms of dryness. The distinction between primary SS (occurring alone) and secondary SS (accompanying conditions like rheumatoid arthritis or lupus) is important, as co-existing symptoms can mask the glandular dryness.
Systemic Effects Beyond Dryness
When the classic dry mouth symptom is absent, the diagnosis is often driven by the presence of extraglandular manifestations (EGM), which are systemic effects occurring outside the salivary and lacrimal glands. These non-dryness symptoms can be highly varied, reflecting Sjögren’s ability to involve nearly any organ system. A common EGM is fatigue and widespread musculoskeletal pain, which can sometimes be mistaken for fibromyalgia.
Joint involvement is also frequent, often presenting as arthralgia (joint pain) that is typically non-erosive. Neurological involvement is another significant EGM, most commonly presenting as peripheral neuropathy, which affects the nerves outside the brain and spinal cord, causing numbness, tingling, or weakness. Central nervous system involvement can also lead to cognitive changes or seizures.
Internal organ involvement, though less common, can be more serious. The kidneys may be affected, leading to renal tubular acidosis, a condition that disrupts the body’s acid-base balance. Pulmonary complications, such as interstitial lung disease, cause inflammation and scarring of the lung tissue, resulting in a chronic dry cough or shortness of breath. Skin manifestations, including vasculitis (palpable purpura), also indicate systemic disease activity. Individuals with SS have an elevated risk for developing hematological issues, most notably B-cell non-Hodgkin lymphoma.
Diagnostic Confirmation Through Objective Testing
Since subjective symptoms of dryness may be misleading or absent, the confirmation of Sjögren’s syndrome relies heavily on objective clinical and laboratory findings. Antibodies to SSA (Ro) and SSB (La) antigens are highly characteristic of SS, and a positive result for anti-SSA/Ro can be a major diagnostic criterion even when dry mouth is not reported.
Objective tests can assess glandular function, such as the Schirmer’s test for tear production or salivary flow tests, though these may be negative or borderline in atypical cases. The gold standard for confirming the disease’s pathology is a minor salivary gland biopsy, typically taken from the inner lip. This procedure looks for characteristic focal lymphocytic sialadenitis—clusters of fifty or more lymphocytes surrounding the ducts and blood vessels in the gland tissue. A positive biopsy result, along with the presence of SSA/Ro antibodies, provides the definitive objective evidence needed to establish a diagnosis of primary Sjögren’s syndrome, acknowledging that the disease is systemic and may not always follow the classic sicca presentation.