Differential Diagnosis for a 2-Month-Old Boy with Persistent Crying
The patient's presentation of persistent crying, refusal to breastfeed, and difficulty consoling, along with specific physical examination findings and laboratory results, guides the differential diagnosis.
Single Most Likely Diagnosis
- C. Septic Arthritis: The patient's symptoms of pain upon movement of the right hip, refusal to feed (which can be a sign of pain or discomfort), fever (38.5 C or 101.3 F), and elevated leukocyte count with a predominance of neutrophils are highly suggestive of septic arthritis. The physical examination finding of the right hip being held in a flexed, abducted, and externally rotated position, along with crying upon palpation of the upper right thigh and resistance to movement of that hip, further supports this diagnosis.
Other Likely Diagnoses
- B. Developmental Dysplasia of the Hip: Although less likely given the acute presentation and fever, developmental dysplasia of the hip could be considered, especially with the finding of the hip being held in a specific position. However, the presence of fever and elevated white blood cell count points more towards an infectious or inflammatory process.
- E. Transient Synovitis: This condition could also present with hip pain and limited range of motion, but it typically does not have such a high fever or significant elevation in white blood cell count as seen in this patient.
Do Not Miss Diagnoses
- A. Acute Leukemia: Although the patient's hemoglobin is slightly low (9.8 g/dL) and there's an elevated white blood cell count, the clinical presentation does not strongly suggest leukemia. However, it's a diagnosis that could be considered, especially if other explanations are ruled out, due to its potential severity.
- D. Sickle Cell Pain Crisis: Given the patient's age and the absence of known sickle cell disease, this is less likely. However, sickle cell disease can present at any age, and a pain crisis could potentially cause the symptoms seen. It's crucial to consider this, especially if the patient is at high risk due to family history or ethnic background.
Rare Diagnoses
- Other rare conditions such as osteomyelitis, bone tumors, or metabolic bone diseases could be considered but are less likely given the information provided. These would typically require additional specific findings or a failure to respond to treatment for more common conditions.