'Sneaky' uninflamed oesophageal candidiasis: morphological clues and comparison with candidiasis associated with inflammation.

Aims: esophagitis is usually readily identified on routine H&E-stained sections as the infection typically presents with prominent acute inflammation as a clue to search for organisms. However, in some cases, inflammation is absent, and detection of organisms relies on the observation of zones exhibiting parakeratosis with a delicate 'flaky' appearance. Our study aimed to establish a correlation between the histomorphology of oesophageal candidiasis and an associated clinical profile.

Methods: We reviewed 53 sequential biopsy specimens from patients with esophagitis collected over 1 year. Biopsies were assessed for acute inflammation, intraepithelial lymphocytosis and lymphoid aggregates. Patients' medical records were reviewed for data on age, gender, race, immune status, smoking, corticosteroid use, HIV status and organ transplantation history. Correlations between these factors and histomorphological patterns were assessed using test.

Results: Of the 53 biopsies, 20 lacked acute inflammation and 33 had it. 15 biopsies showed both acute and lymphoid inflammation and 5 showed lymphocytosis only. Among 16 smokers, 6 (37%) had acute inflammation and 10 (63%) had parakeratosis. In non-smokers, 24 (71%) had acute inflammation and 10 (29%) had parakeratosis. A significant correlation was found between smoking and absence of acute neutrophilic infiltration (p=0.025), but no other clinical factor was associated with inflammatory patterns.

Conclusions: esophagitis can be uninflamed with 'flaky' parakeratosis or associated with acute inflammation or lymphocytosis with or without neutrophilic infiltration. Inflammation was often absent in smokers, suggesting synergistic local immunosuppressive effect is this overall immunosuppressed population.