What are the causes and treatments of a strawberry tongue?

Strawberry Tongue: Causes and Treatment

Primary Causes

Strawberry tongue is most commonly associated with Kawasaki disease, scarlet fever (Group A Streptococcal infection), toxic shock syndrome, and multisystem inflammatory syndrome in children (MIS-C) associated with SARS-CoV-2. 1, 2

Kawasaki Disease

• Strawberry tongue appears as erythema with prominent fungiform papillae, indistinguishable from streptococcal scarlet fever 1
• Occurs alongside fever ≥5 days plus ≥4 of the following: bilateral conjunctival injection, polymorphous rash, extremity changes (erythema/edema of hands/feet), cervical lymphadenopathy ≥1.5 cm, and oral mucosal changes (red/cracked lips, diffuse oropharyngeal erythema) 1
• Predominantly affects children under 5 years (80% of cases), with male-to-female ratio of 1.5:1 1
• Critical pitfall: Diagnosis can be made before day 5 of fever if classic features are present by experienced observers 1

Scarlet Fever (Group A Streptococcal Infection)

• Presents with initially white-coated tongue that becomes bright red with prominent papillae 2
• Accompanied by fever, sore throat, and characteristic sandpaper-like rash 2
• More common in children aged 5-15 years 2

MIS-C (SARS-CoV-2 Associated)

• Shares overlapping features with Kawasaki disease including strawberry tongue, conjunctival injection, rash, and extremity changes 1
• Key distinguishing features: broader age range, more prominent GI/neurologic symptoms, higher frequency of shock and cardiac dysfunction, lower platelet counts, and higher CRP levels compared to classic Kawasaki disease 1
• Temporally associated with SARS-CoV-2 infection, emerging 2-6 weeks after peak COVID-19 incidence 1

Toxic Shock Syndrome

• TSST-1-mediated disease can present with strawberry tongue showing chronological changes 3
• Associated with systemic toxicity and multiorgan involvement 3

Diagnostic Approach

Initial Evaluation

• Measure fever duration and document all mucocutaneous findings systematically 1
• Examine for conjunctival injection (bulbar, non-purulent), oral changes (lip cracking, oropharyngeal erythema), rash pattern, extremity changes, and lymphadenopathy 1
• Obtain throat culture/rapid strep test to rule out scarlet fever 2
• In patients with epidemiologic link to SARS-CoV-2, send SARS-CoV-2 PCR and serology (IgG, IgM, IgA) 1

Laboratory Workup for Suspected Kawasaki Disease/MIS-C

• If fever >5 days with 2-3 classic symptoms: measure CRP and ESR first 1
• If inflammatory markers elevated: obtain serum albumin, transaminases, complete blood count, and urinalysis 1
• Echocardiography should be performed even if <10 days of illness when Kawasaki disease strongly suspected 1
• EKG, BNP, and troponin T levels to assess cardiac involvement 1

Treatment

Kawasaki Disease

• First-line: IVIG 2 g/kg as single infusion (Grade A evidence) 1
• High-dose aspirin 80-100 mg/kg/day divided into 4 doses, given concurrently with IVIG 1
• Treatment must be initiated promptly to decrease the ~20% risk of coronary artery abnormalities 1
• Fever typically resolves within 2 days of appropriate therapy 1

Scarlet Fever

• Appropriate antibiotic therapy targeting Group A Streptococcus 2
• Penicillin remains first-line treatment 2

MIS-C

• Patients presenting with shock, respiratory distress, neurologic changes, or Kawasaki disease features require hospital admission 1
• Management requires multidisciplinary team including pediatric rheumatology, cardiology, infectious disease, and hematology 1
• Treatment parallels Kawasaki disease with IVIG and aspirin, though specific protocols may vary 1

Candidiasis (If Present)

• Antifungal therapy for candidal infections causing bright red tongue after white plaques removed 2
• Particularly important in immunocompromised patients 2

Critical Clinical Pitfalls

• Do not wait for all 5 principal features to be present simultaneously—they appear sequentially and may not coexist 4
• Incomplete Kawasaki disease with <4 principal features can still cause coronary artery aneurysms—diagnose if coronary abnormalities detected on echocardiography 1
• Younger MIS-C patients more likely present with Kawasaki-like features; older children more likely develop myocarditis and shock 1
• MIS-C patients without Kawasaki features can still develop coronary artery aneurysms 1