Differential Diagnosis for Fungal Infections Causing a Lung Tree in Bud Pattern with AKI in South Dakota

• Single Most Likely Diagnosis
  • Histoplasmosis: This fungal infection is common in the Midwest, including South Dakota, and can cause a "tree-in-bud" pattern on lung imaging due to its propensity to cause bronchiolitis and peribronchiolar inflammation. Acute kidney injury (AKI) can occur, especially in severe cases or as part of a systemic inflammatory response.
• Other Likely Diagnoses
  • Blastomycosis: Another fungal infection that can cause lung disease with a tree-in-bud pattern, Blastomycosis is found in the Midwest and can lead to AKI, particularly in disseminated disease.
  • Coccidioidomycosis: While more commonly associated with the southwestern United States, Coccidioidomycosis can cause a tree-in-bud pattern and AKI, especially in immunocompromised patients or those with severe disease.
• Do Not Miss Diagnoses
  • Invasive Aspergillosis: Although less common in immunocompetent individuals, Invasive Aspergillosis can cause a tree-in-bud pattern and is associated with high mortality, especially if not promptly treated. AKI can occur due to the disease itself or as a result of antifungal therapy.
  • Mucormycosis: A rare but deadly fungal infection that can cause lung disease and AKI, particularly in diabetic or immunocompromised patients. Its inclusion in the differential is crucial due to its high mortality rate and the need for prompt treatment.
• Rare Diagnoses
  • Cryptococcosis: While it can cause lung disease, Cryptococcosis is less commonly associated with a tree-in-bud pattern. However, in immunocompromised patients, it can lead to severe disease, including AKI.
  • Paracoccidioidomycosis: More commonly found in Central and South America, Paracoccidioidomycosis is a rare cause of fungal infection in the United States but can cause lung disease and AKI in severe cases.