Differential Diagnosis
- Single most likely diagnosis
- Pulmonary embolism with mild presentation: The patient has a mildly elevated D-dimer (1.91) and no acute cardiopulmonary findings on the chest X-ray, but the CT angiography (CTA) of the chest shows mild bilateral bronchial wall thickening. Although the BNP is low (<10), which decreases the likelihood of heart failure, and troponin is only slightly elevated (0.02), the combination of these findings with low lung volumes could suggest a mild or early pulmonary embolism.
- Other Likely diagnoses
- Infectious or inflammatory bronchitis: The CTA chest finding of mild bilateral bronchial wall thickening supports this diagnosis, and the presence of occasional bacteria in the urinalysis could indicate a urinary tract infection (UTI) which sometimes co-exists with or complicates respiratory infections.
- Urinary tract infection (UTI) or kidney stones: The urinalysis showing RBC 6-10, bacteria (occ 0-10), and moderate blood in the urine suggests a possible UTI or kidney stones, which could be the primary issue, with the respiratory findings being secondary or unrelated.
- Do Not Miss (ddxs that may not be likely, but would be deadly if missed.)
- Pulmonary embolism (even though listed as the single most likely, its importance warrants repetition here): Given the potential for a high mortality rate if missed, it's crucial to thoroughly investigate any possibility of pulmonary embolism, especially with the elevated D-dimer.
- Sepsis: Although not directly indicated by the provided lab results, the presence of bacteria in the urine and the possibility of an infectious process in the lungs means sepsis should be considered, especially if the patient shows signs of systemic infection.
- Rare diagnoses
- Goodpasture syndrome: This is a rare autoimmune disease that can cause both renal and pulmonary manifestations, including hematuria (blood in the urine) and pulmonary infiltrates or hemorrhage. The presence of blood in the urine and the lung findings could, in a rare case, suggest this diagnosis.
- Vasculitis (e.g., Wegener's granulomatosis): Another rare condition that could explain both the renal and pulmonary findings, characterized by inflammation of the blood vessels, which could lead to the observed symptoms and lab results.