Can celiac disease present in a 33‑year‑old adult?

Can Celiac Disease Present at Age 33?

Yes, celiac disease absolutely can—and frequently does—present at age 33 or any adult age. In fact, the majority of celiac disease cases remain undiagnosed until adulthood, demonstrating that the disease commonly manifests late in life 1.

Key Evidence Supporting Adult-Onset Presentation

Celiac disease can occur at any age, and clinicians should maintain a high level of suspicion that it may be present in both sexes and across a wide variety of clinical circumstances 2, 1. The historical view that celiac disease was predominantly a childhood disorder with classic malabsorption has been completely overturned 2, 3.

Age Distribution in Diagnosed Cases

• In one large adult cohort study, the mean age at diagnosis was 33 years (range 18-65 years), with 74% being women 4
• Until the 1980s, celiac disease was incorrectly considered rare and mainly affecting children, but it has since been shown to occur at any age 2
• The incidence of adult celiac disease diagnosis has increased dramatically—from 0.7-2 per 100,000 per year in the 1990s to 3.5-10.3 per 100,000 in recent years 4

Clinical Presentation in Adults Age 33

Common Manifestations at This Age

Adult presentations differ substantially from childhood and include 4:

• Diarrhea (55% of cases)
• Abdominal pain (40% of cases)
• Iron-deficiency anemia (48.5% of cases) 4
• Weight loss (22% of cases)
• Elevated transaminases (38% of cases)
• Dyspepsia (19% of cases)

Atypical and Extraintestinal Features

Many adults present with non-gastrointestinal symptoms rather than classic malabsorption, which often delays diagnosis 2, 1. These include:

• Unexplained iron-deficiency anemia (even in menstruating women) 1
• Abnormal liver function tests 5
• Bone disease and osteoporosis 5
• Neuropathy and ataxia 2
• Depression 2
• Skin disorders 5

Critical Diagnostic Considerations

When to Suspect Celiac Disease in a 33-Year-Old

Screen for celiac disease in the following scenarios 1:

• Unexplained iron-deficiency anemia (prevalence 3-9% in endoscopic studies)
• Unexplained elevated transaminases (prevalence 1.5-9%)
• Osteoporosis or osteomalacia, particularly if premature
• Type 1 diabetes mellitus (prevalence 2-5% in adults)
• First-degree relatives of celiac patients (prevalence ~10%)

Common Diagnostic Pitfalls

Atypical manifestations and low clinical suspicion can delay diagnosis for years 4. Key pitfalls include:

• Only approximately 24% of individuals with celiac disease are diagnosed, creating a "celiac iceberg" of undiagnosed cases 1, 6
• Symptoms may be subtle and not clearly related to gastrointestinal disease 3
• Patients with ferropenic anemia unresponsive to treatment should be screened for celiac disease 4
• Testing patients already on a gluten-free diet will yield false-negative results 1, 6

Diagnostic Approach

The diagnostic workup should include 1, 5:

1. Serologic testing: Measure IgA tissue transglutaminase (tTG) antibodies with documentation of normal total serum IgA levels
2. If IgA deficient: Use IgG tTG and deamidated gliadin peptide antibodies
3. Confirmatory biopsy: Duodenal mucosal biopsies during upper endoscopy (both serology and biopsy must be performed on a gluten-containing diet) 5

The sensitivity and specificity of IgA anti-tissue transglutaminase in adults are 90.7% and 87.4% respectively, while IgA endomysial antibodies show 88.0% sensitivity and 99.6% specificity 1.

Bottom Line

There is no age cutoff for celiac disease presentation—it is a lifelong condition that can be triggered at any point in adulthood 2, 7. Age 33 falls well within the typical range for adult diagnosis, and the disease should be actively considered in any adult with compatible symptoms or associated conditions, regardless of age 1, 3.