Differential Diagnosis for Centripetal Rashes Starting on the Hands and Feet with Sore Throat

• Single Most Likely Diagnosis

  • Scarlet Fever: This condition, caused by Group A beta-hemolytic streptococci, typically presents with a centripetal rash (starting on the extremities and moving towards the trunk), sore throat, and fever. The rash often feels like sandpaper and is accompanied by a "strawberry tongue."

• Other Likely Diagnoses

  • Kawasaki Disease: An acute febrile illness of childhood characterized by a rash, which can be centripetal, along with fever, conjunctivitis, cervical lymphadenopathy, and changes in the lips and oral cavity. The sore throat can be part of the initial presentation.
  • Toxic Shock Syndrome (TSS): Although more commonly associated with a diffuse rash, TSS can present with a centripetal rash pattern. It is characterized by high fever, sore throat, and the potential for rapid progression to severe illness, including shock and organ failure.
  • Viral Exanthems (e.g., Enterovirus, Adenovirus): Various viral infections can cause rashes that start on the hands and feet and are accompanied by systemic symptoms like sore throat. These are often self-limiting but can be part of a broader differential.

• Do Not Miss Diagnoses

  • Meningococcemia: A severe infection caused by Neisseria meningitidis, which can present with a rash (often petechial or purpuric but can be variable), fever, and sore throat. It is critical to identify and treat promptly due to its high mortality rate if left untreated.
  • Rocky Mountain Spotted Fever (RMSF): Caused by Rickettsia rickettsii, transmitted by ticks. It presents with fever, headache, and a characteristic rash that starts on the hands and feet and can be accompanied by a sore throat. Early diagnosis and treatment are crucial to prevent severe outcomes.

• Rare Diagnoses

  • Secondary Syphilis: Can present with a variety of rash patterns, including a centripetal distribution, along with systemic symptoms like sore throat. It's less common but should be considered, especially in sexually active individuals or those with risk factors for syphilis.
  • Rat-bite Fever: Caused by Streptobacillus moniliformis or Spirillum minus, transmitted through the bites of infected rodents. It presents with fever, rash (which can start on the hands and feet), and can include sore throat among its symptoms. It's rare but should be considered in individuals with exposure to rodents.