Differential Diagnosis
- Single most likely diagnosis: + Hand, Foot, and Mouth Disease (HFMD): This diagnosis is likely due to the presence of mouth ulcers, red blisters on the hands, and the progression to the arms. The symptoms of tiredness, swollen tongue, and headache are also consistent with HFMD.
- Other Likely diagnoses: + Herpes Simplex Virus (HSV) infection: The presence of mouth ulcers and red blisters could be indicative of an HSV infection, particularly if the patient has a history of cold sores or genital herpes. + Impetigo: A bacterial skin infection that can cause red blisters and sores, which could be a possible diagnosis given the patient's symptoms. + Erythema Multiforme: An immune-mediated condition that can cause skin lesions and mouth ulcers, which could be a possible diagnosis given the patient's symptoms.
- Do Not Miss (ddxs that may not be likely, but would be deadly if missed.): + Stevens-Johnson Syndrome (SJS): A rare but life-threatening condition that can cause skin lesions, mouth ulcers, and other systemic symptoms. Although it is unlikely, it is crucial to consider SJS due to its potential severity. + Toxic Epidermal Necrolysis (TEN): A severe skin condition that can cause widespread skin lesions and detachment, which can be life-threatening if not promptly treated.
- Rare diagnoses: + Pemphigus Vulgaris: A rare autoimmune disorder that can cause blistering skin lesions and mouth ulcers. + Aphthous Stomatitis: A rare condition that can cause recurrent mouth ulcers, which could be a possible diagnosis if the patient has a history of similar symptoms. + Autoimmune disorders (e.g., Lupus, Rheumatoid Arthritis): Although rare, these conditions can cause a range of symptoms, including skin lesions, mouth ulcers, and systemic symptoms, and should be considered in the differential diagnosis.