Corpora amylacea in cervicovaginal smears

From corpora amylacea to wasteosomes: History and perspectives

Corpora amylacea (CA) have been described in several human organs and have been associated with ageing and several pathological conditions. Although they were first discovered two centuries ago, their function and significance have not yet been identified. Here, we provide a chronological summary of the findings on CA in various organs and identify their similarities. After collecting and integrating these findings, we propose to consider CA as waste containers created by specific cells, which sequester waste products and foreign products, and assemble them within a glycan structure. The containers are then secreted into the external medium or interstitial spaces, in this latter case subsequently being phagocytosed by macrophages. This proposal explains, among others, why CA are so varied in content, why only some of them contain fibrillary amyloid proteins, why all of them contain glycan structures, why some of them contain neo-epitopes and are phagocytosed, and why they can be intracellular or extracellular structures. Lastly, in order to avoid the ambiguity of the term amyloid (which can indicate starch-like structures but also insoluble fibrillary proteins), we propose renaming CA as "wasteosomes", emphasising the waste products they entrap rather than their misleading amyloid properties.

Corpora amylacea in sputum smears: Incidence and clinical significance

OBJECTIVE

To examine conventional sputum smears for the presence of corpora amylacea (CA), determining their incidence and clinical significance.

METHODS

A retrospective 4-year cohort study was undertaken of sputum samples from 1176 consecutive patients for the presence of CA. Variables such as age, sex, smoking status, and the presence or absence of haemoptysis were extracted from the medical record. A random group of 50 patients was selected as a control group, and a random group of 50 patients whose ages were below 49 years was also included as an age-based control.

RESULTS

A total of 1075 of the initial cohort of consecutive patients were included in the study. from these, there were 6898 sputum smears, of which 1.91% (132 smears) contained CA, corresponding to 9.86% of the cohort of patients (106 patients). There was a strong, positive, statistically significant correlation between age and CA presence (τ_b  = .402, P < .001), which supports that CA are associated with older patients. The results of a binary logistic regression indicated that there was a significant association between age, diagnosis of chronic obstructive pulmonary disease and CA presence (χ²  = 49.051, df = 2, P < .001).

CONCLUSIONS

The presence of CA in sputum smears is related to age, being much more frequent in older people. Moreover, CA are related to non-neoplastic lung diseases.