Postpartum pulmonary micronodules and thyroid cystic nodules in a COVID-19 vaccinated patient: A CARE-compliant case report.

RATIONALE: This study presents the first documented case suggesting a potential association between prepregnancy administration of 4 doses of mRNA corona virus disease-19 vaccine and the development of postpartum multi-organ nodules, including pulmonary micronodules and thyroid cysts. The purpose of this report is to delineate a clinical scenario involving 3 interrelated factors: vaccine-induced sustained immune activation, inadequately managed moderate anxiety during pregnancy, and significant lifestyle alterations such as a gluten- and dairy-free diet coupled with sleep deprivation. The significance of this case lies in its novel exposure profile and undocumented long-term implications, offering critical insights that may inform future reproductive health guidance and risk counseling.

PATIENT CONCERNS: A 34-year-old women who presented with incidental findings of asymptomatic bilateral diffuse pulmonary micronodules and thyroid cystic nodules (TI-RADS 1) during routine 6-month postpartum imaging.

DIAGNOSES: Chest computed tomography and thyroid ultrasound confirmed multiple pulmonary micronodules coexisting with benign thyroid cystic nodules. Serial investigations ruled out metastasis, granulomatous disease, and classic autoimmune disorders.

INTERVENTIONS: A diagnostic monitoring strategy was implemented, including serial pulmonary computed tomography (6-month follow-ups) and thyroid ultrasound surveillance (12-month follow-ups), complemented by lifestyle rebalancing (gradual exercise reintroduction/sleep optimization) and psychological counseling for health-related anxiety. Pharmacological intervention was withheld to observe the natural evolution of nodule regression and immune homeostasis restoration.

OUTCOMES: During the ongoing follow-up period, there were no other improvements or deterioration developments.

LESSONS: This case suggests prepregnancy vaccine immune imprinting may become activated under gestational stress, potentially triggering subclinical inflammation via the hypothalamic-pituitary-adrenal axis-gut microbiota-cytokine network. Consequently, we propose the "V-SLAM" clinical framework (vaccine history/stress biomarkers/lifestyle factors/autoimmunity screening/multidisciplinary consultation), emphasizing the integration of vaccination records and psychological resilience assessment into preconception counseling, with cross-pregnancy immune-metabolic monitoring for high-risk women.