Differential Diagnosis for Cellulitis, Mouth Sores, and Joint Pain
Single Most Likely Diagnosis
- Infectious cellulitis with superimposed viral infection (e.g., herpes simplex): The patient is already taking Augmentin, which suggests a bacterial infection. The presence of mouth sores could indicate a viral infection, and joint pain could be related to the bacterial infection or a separate condition.
Other Likely Diagnoses
- Lyme disease: This condition can cause cellulitis (erythema migrans), joint pain, and potentially mouth sores if there are associated systemic symptoms.
- Streptococcal infection: Streptococcal infections can cause cellulitis and may be associated with joint pain and mouth sores, especially if the infection is severe or if there is an associated condition like acute rheumatic fever.
- Inflammatory arthritis (e.g., rheumatoid arthritis): This could explain the joint pain, and some patients with inflammatory arthritis may develop secondary infections or mouth sores due to immunosuppression or as part of the disease process.
Do Not Miss Diagnoses
- Endocarditis: Although less likely, endocarditis can present with a wide range of symptoms including joint pain, skin infections (like cellulitis), and potentially mouth sores if there are embolic phenomena affecting the oral mucosa.
- Lupus or other autoimmune diseases: These conditions can cause a wide range of symptoms including joint pain, mouth sores, and potentially skin infections. Missing these diagnoses could lead to significant morbidity.
- Osteomyelitis or septic arthritis: These are serious infections that could present with localized pain (which might be perceived as joint pain) and could be associated with cellulitis or mouth sores in the context of a systemic infection.
Rare Diagnoses
- Behçet's disease: A rare condition characterized by recurrent mouth sores, genital sores, and inflammation in parts of the eye. It can also cause joint pain and skin lesions that might resemble cellulitis.
- Sarcoidosis: Although rare, sarcoidosis can cause a wide range of symptoms including joint pain, skin lesions, and potentially mouth sores, especially if there is significant systemic involvement.
- Neutropenia or agranulocytosis: Conditions that could increase the risk of infections (including cellulitis) and might be associated with mouth sores. These could be drug-induced (e.g., by certain antibiotics) or due to an underlying condition.