Differential Diagnosis for Fever with Left Upper Lobe Consolidations and Mediastinal Lymph Nodes
- Single Most Likely Diagnosis
- Community-Acquired Pneumonia (CAP): The presence of fever, especially worsening in the evening, along with left upper lobe consolidations on CT thorax, strongly suggests pneumonia. The increase in WBC count and elevated CRP further support an infectious process. CAP is a common condition that matches these clinical and radiological findings.
- Other Likely Diagnoses
- Tuberculosis (TB): Given the involvement of the left upper lobe and the presence of mediastinal lymph nodes, TB should be considered, especially if the patient has risk factors such as exposure history, immunocompromised status, or resides in an area with high TB prevalence.
- Lymphoma: Although less common, lymphoma could present with fever, lymphadenopathy (including mediastinal lymph nodes), and pulmonary infiltrates. The normal WBC count initially might not rule out lymphoma, as it can have a varied presentation.
- Do Not Miss Diagnoses
- Sarcoidosis: This condition can cause lymphadenopathy, pulmonary infiltrates, and systemic symptoms like fever. It's crucial to consider sarcoidosis due to its potential for significant morbidity if not diagnosed and treated appropriately.
- Histoplasmosis or Other Fungal Infections: In endemic areas, histoplasmosis can present with similar symptoms and radiographic findings. Missing this diagnosis could lead to severe consequences, especially in immunocompromised patients.
- Rare Diagnoses
- Wegener's Granulomatosis (Granulomatosis with Polyangiitis, GPA): This is a rare autoimmune disorder that can cause pulmonary nodules, lymphadenopathy, and systemic symptoms. It's essential to consider GPA due to its potential for severe organ damage if left untreated.
- Erdheim-Chester Disease: A rare form of histiocytosis that can involve the lungs and lymph nodes, presenting with systemic symptoms. Although rare, its consideration is important due to its distinct treatment and prognosis.