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PFAPA syndrome — Clinical Guidelines

Overview

PFAPA syndrome, characterized by periodic episodes of fever, aphthous stomatitis, pharyngitis, and cervical adenitis, is the most common recurrent fever syndrome in childhood 1. Its etiology remains unknown, but immunological and microbiological factors are implicated 3 4 6.

Diagnosis

Key Diagnostic Criteria: Fever lasting 3-6 days, accompanied by aphthous stomatitis, pharyngitis, and cervical adenitis, recurring without systemic symptoms between episodes 1.

Recommended Tests: Blood cell counts showing variable neutrophil levels (normal, neutropenia, neutrophilia) 1.

Inflammatory Markers: Elevated inflammatory factors may be present 1.

Tonsillar Biopsy: Altered expression of TLR-1 and TLR-2 in tonsillar tissue suggests immune dysregulation 2.

Microbiome Analysis: Differences in tonsillar microbiota, including higher prevalence of cyanobacteria in PFAPA patients 4.

Genital Ulcers: Rarely, genital ulcers can be a presenting symptom 5.

Management

First-Line Treatments:

- Nonsteroidal Anti-Inflammatory Drugs (NSAIDs): Commonly used to manage symptoms 7. - Prednisolone: Effective in reducing fever; higher doses (2 mg/kg/day) show quicker response compared to lower doses (0.5 mg/kg/day) 8.

Adjunctive Treatments:

- Tonsillectomy: May offer long-term remission in some patients, comparable to medical treatment 7. - Oxidative Stress Management: Consideration of antioxidants may be warranted given elevated oxidative stress in PFAPA patients 6.

Special Populations

Pediatrics: PFAPA predominantly affects children, with a peak age range of 3-4 years 1.

Comorbidities: No specific management adjustments noted for comorbidities; focus remains on symptom control 7.

Key Recommendations

Use NSAIDs for symptom management during acute episodes (Evidence: Moderate 7).

Consider prednisolone for severe episodes, with higher doses (2 mg/kg/day) for faster fever reduction (Evidence: Weak 8).

Evaluate tonsillectomy as a potential long-term solution for refractory cases, though evidence is weak (Evidence: Weak 7 9).

Monitor oxidative stress parameters in patients with persistent symptoms to guide adjunctive therapy (Evidence: Weak 6).

Avoid routine tonsillectomy due to insufficient strong evidence supporting its efficacy (Evidence: Weak 9).

References

1 Abbasi E, Mamizadeh N, Seidkhani H, Khoshnood S, Mohamadi J. Evaluation of the Levels of Blood Cells, Vitamin D, and Inflammatory Factors in Children with PFAPA Syndrome. Clinical laboratory 2023. link 2 Gazi U, Ozkayalar H, Mujahed MIM, Tosun O, Dalkan C, Sanlidag B et al.. Altered tonsillar toll-like receptor (TLR)-1 and TLR-2 expression levels between periodic fever, aphthous stomatitis, pharyngitis and cervical adenitis (PFAPA), and group A beta-hemolytic streptococcal (GAβHS) recurrent tonsillitis patients. International journal of pediatric otorhinolaryngology 2021. link 3 Førsvoll J, Kristoffersen EK, Øymar K. The immunology of the periodic fever, aphthous stomatitis, pharyngitis and cervical adenitis syndrome; what can the tonsils reveal. A literature review. International journal of pediatric otorhinolaryngology 2020. link 4 Tejesvi MV, Uhari M, Tapiainen T, Pirttilä AM, Suokas M, Lantto U et al.. Tonsillar microbiota in children with PFAPA (periodic fever, aphthous stomatitis, pharyngitis, and adenitis) syndrome. European journal of clinical microbiology & infectious diseases : official publication of the European Society of Clinical Microbiology 2016. link 5 Scattoni R, Verrotti A, Rinaldi VE, Paglino A, Carelli A, D'Alonzo R. Genital ulcer as a new clinical clue to PFAPA syndrome. Clinical and experimental dermatology 2015. link 6 Tuğrul S, Doğan R, Kocyigit A, Torun E, Senturk E, Ozturan O. DNA damage and oxidative status in PFAPA syndrome. Auris, nasus, larynx 2015. link 7 Vigo G, Martini G, Zoppi S, Vittadello F, Zulian F. Tonsillectomy efficacy in children with PFAPA syndrome is comparable to the standard medical treatment: a long-term observational study. Clinical and experimental rheumatology 2014. link 8 Yazgan H, Gültekin E, Yazıcılar O, Sagun ÖF, Uzun L. Comparison of conventional and low dose steroid in the treatment of PFAPA syndrome: preliminary study. International journal of pediatric otorhinolaryngology 2012. link 9 Leong SC, Karkos PD, Apostolidou MT. Is there a role for the otolaryngologist in PFAPA syndrome? A systematic review. International journal of pediatric otorhinolaryngology 2006. link

PFAPA syndrome