Several features in this patient's presentation raised suspicion for amyloidosis:
- Characteristic multi-organ involvement - The combination of heart failure, renal impairment, and peripheral neuropathy is highly suggestive of a systemic process.
- Cardiac findings - The discrepancy between thickened ventricular walls on echocardiography and low voltage complexes on ECG is relatively specific for infiltrative cardiomyopathy. The "speckled" or "granular sparkling" appearance of the myocardium on echocardiography, while not entirely specific, is characteristic of amyloid deposition.
- Physical examination findings - Macroglossia with scalloped edges and periorbital purpura (often called "raccoon eyes") are classic findings in AL amyloidosis. The waxy skin papules represent cutaneous amyloid deposits.
- Historical clues - Bilateral carpal tunnel syndrome (noted in past medical history) often precedes cardiac amyloidosis by several years and represents an early manifestation of amyloid deposition.
- Laboratory abnormalities - The combination of proteinuria, elevated cardiac biomarkers despite preserved ejection fraction, and abnormal serum free light chain ratio suggested a plasma cell dyscrasia with AL amyloidosis.
- Response to treatment - The patient's poor response to standard heart failure management and fluid resuscitation suggested an underlying pathology beyond conventional heart failure.
- Hypotension out of proportion to cardiac function - Autonomic neuropathy and small vessel involvement in amyloidosis often leads to hypotension that is more severe than would be expected from the measured ejection fraction.
This constellation of findings prompted the treating team to pursue specific testing for amyloidosis, including tissue diagnosis with Congo red staining and typing of the amyloid protein.
