Kikuchi-Fujimoto Disease Following COVID-19 Infection in a 7-Year-Old Girl: A Case Report and Literature Review

COVID-19 vaccine-associated lymphadenopathy: a review

Following the introduction of RNA-based vaccines, COVID-19 vaccine-associated clinical lymphadenopathy (C19-LAP) has been reported as a side effect. Moreover, subclinical lymphadenopathy detected on imaging (SLDI) has also been observed, mainly as incidental findings while performing screening tests on oncological patients. In these cases, surgical lymphadenectomy, fine-needle aspiration cytology (FNAC) and core needle biopsy (CNB) have been used as a valuable diagnostic tool for SLDI and C19-LAP. In this review the clinical, histologic and cytologic features of SLDI and C19-LAP have been investigated. A search for studies that reported on C19-LAP and SLDI histopathology and cytopathology was performed on PubMed and Google Scholar, on 11 January 2023. Thirty-one reports on SLDI and C19-LAP were retrieved and included in a pooled analysis. In total, we included 54 patients with a median age of 47 years. In our research, surgical excision, CNB and/or FNAC of C19-LAP or SLDI enlarged lymph nodes have been performed in 54 cases. Of all cases, only two metastases were diagnosed and one case was diagnosed as reactive hyperplasia with atypical follicles. The remaining cases were reactive lymphadenopathy (28 cases), follicular hyperplasia (13 cases), Kikuchi-Fujimoto disease (6 cases), granulomatous lymphadenitis (2 cases), eosinophilic lymph node abscesses (1 case), Langherans cell histiocytosis (1 case), Rosai-Dorfman disease (1 case). SLDI and C19-LAP have represented a diagnostic dilemma, especially in oncologic patients. The role of different diagnostic tools for SLDI and C19-LAP has been discussed.

The Role of the European Medicines Agency in the Safety Monitoring of COVID-19 Vaccines and Future Directions in Enhancing Vaccine Safety Globally

The European Union (EU) regulatory network was at the forefront of the safety monitoring of COVID-19 vaccines during the pandemic. An unprecedented number of case reports of suspected adverse reactions after vaccination called for huge efforts for the assessment of this safety information, to ensure that any possible risks were detected and managed as early as possible, while ruling out coincidental but temporally related adverse health outcomes. We describe the role of the European Medicines Agency alongside the EU regulatory network in the safety monitoring of the COVID-19 vaccines, and provide an insight into challenges, particularities and outcomes of the scientific assessment and regulatory decisions in the complex, dynamic international environment of the pandemic. We discuss the flexible procedural tools that were used to ensure an expedited scientific assessment of safety issues, and subsequent updates of the product information (i.e., labelling) when available evidence (e.g., spontaneous reports, findings from observational studies and/or scientific literature) suggested that causal association is at least a reasonable possibility. The safety monitoring was accompanied by enhanced transparency measures, proactive communication, and easy access to information, which played a key role in public reassurance. The pandemic has been a powerful booster for worldwide collaboration, exchange of information and work-sharing. The safety monitoring of COVID-19 vaccines continues, and the lessons learned will be applied in future safety reviews, as well as future health emergencies.

Kikuchi-Fujimoto disease type lymph node reaction with increased plasmacytoid dendritic cells may appear as a side effect following COVID-19 vaccination: Report of a case and literature review

Subsequent to mass vaccination programs against COVID-19, diverse side effects have been described, both at the injection site, such as pain, redness and swelling, and systemic effects such as fatigue, headache, muscle or joint pain. On rare occasions, a lymphadenopathic syndrome may develop, raising the clinical suspicion of a lymphoproliferative disorder. We present the case of a 30-year-old woman who developed self-limiting left axillary lymphadenopathy following COVID-19 vaccination. To date, only seven similar cases with a complete clinicopathological description have been published, and fourteen cases have been notified to the European adverse events databases (Eudravigilance) in relationship with vaccination against COVID-19. It is important to be aware of this potential complication when a lymphadenopathic syndrome develops following vaccination, to avoid unnecessary treatment.

Kikuchi-Fujimoto disease: A comprehensive review

Kikuchi-Fujimoto disease, a rare form of necrotizing lymphadenitis, is an uncommon, benign, self-limiting disorder of obscure etiology. It affects mostly young adults of both genders. Clinically, it presents with fever and lymphadenopathy of a firm to rubbery consistency frequently involving cervical lymph nodes while weight loss, splenomegaly, leucopenia, and elevated erythrocyte sedimentation rate feature in severely affected patients. Cutaneous involvement occurs in about 30%-40% of cases as facial erythema and nonspecific erythematous papules, plaques, acneiform or morbilliform lesions of great histologic heterogeneity. Both Kikuchi-Fujimoto disease and systemic lupus erythematosus share an obscure and complex relationship as systemic lupus erythematosus may occasionally precede, develop subsequently, or sometimes be associated concurrently with Kikuchi-Fujimoto disease. It is often mistaken for non-Hodgkin lymphoma while lupus lymphadenitis, cat-scratch disease, Sweet's syndrome, Still's disease, drug eruptions, infectious mononucleosis, and viral or tubercular lymphadenitis are other common differentials. Fine needle aspiration cytology mostly has features of nonspecific reactive lymphadenitis and immunohistochemistry studies usually show variable features of uncertain diagnostic value. Since its diagnosis is exclusively from histopathology, it needs to be evaluated more carefully; an early lymph node biopsy will obviate the need for unnecessary investigations and therapeutic trials. Its treatment with systemic corticosteroids, hydroxychloroquine, or antimicrobial agents mostly remains empirical. The article reviews clinicoepidemiological, diagnostic, and management aspects of KFD from the perspective of practicing clinicians.