Differential Diagnosis for 3-Month-Old with Bilateral Arm Eczema
- Single Most Likely Diagnosis
- Atopic Dermatitis (Eczema): This is the most common skin condition in infants, often presenting with bilateral and symmetrical lesions on the arms, face, and legs. The age of the patient and the location of the lesions make this diagnosis highly likely.
- Other Likely Diagnoses
- Contact Dermatitis: This could be due to an allergic reaction or irritation from substances like soaps, lotions, or fabrics that come into contact with the skin. Given the bilateral nature, it might be less likely but still possible, especially if the infant has been exposed to new products.
- Seborrheic Dermatitis: Although more commonly associated with scalp lesions (cradle cap), it can also affect other oily areas of the body and might present similarly to eczema in infants.
- Do Not Miss Diagnoses
- Scabies: While less common in this age group, scabies can present with severe itching and skin lesions. It's highly contagious and requires prompt treatment to prevent spread.
- Congenital Syphilis: This condition can cause a variety of skin rashes, including those that might resemble eczema. Given the potential severity and the importance of early treatment, it's crucial not to miss this diagnosis.
- Rare Diagnoses
- Wiskott-Aldrich Syndrome: A rare genetic disorder characterized by eczema, thrombocytopenia, and recurrent infections. The presence of other symptoms like bleeding or recurrent infections would make this more likely.
- Netherton Syndrome: A rare genetic disorder that includes ichthyosiform dermatitis (similar to eczema), hair shaft abnormalities, and immune system defects. The specific combination of skin findings and other systemic symptoms would guide towards this diagnosis.
- Zinc Deficiency: Can cause skin lesions that resemble eczema, along with other symptoms like hair loss and diarrhea. This would be more likely in infants with dietary deficiencies or specific conditions affecting zinc absorption.