Methods
Blood exams revealed increased levels of serum aspartate
aminotransferase (AST), alanine aminotransferase (ALT), gamma-glutamyl
transferase (GGT), lactate dehydrogenase (LDH), D-Dimer,
high-sensitivity troponin (stable after 3 hours). Arterial blood gas
analysis was normal and SARS Cov-2 RNA testing of the swab was negative.
Chest X-Ray documented thickened smoothly interlobular septae in the
right parahilar, subtle parenchymal hypodiaphania on the left basal area
and blunting of the costophrenic angles. After blood cultures and swabs
collection for St. Aureus Methicillin-Resistent , empiric
antibiotic therapy with piperacillin/tazobactam and daptomycin was then
started. Compression ultrasonography of lower extremity outlined partial
and segmental incompressibility of the right popliteal vein compatible
with subacute deep vein thrombosis (DVT) with partial recanalization.
DVT treatment with low-molecular-weight heparin was immediately started.
Upon admission to our Unit the patient was in fair clinical condition.
His heart rate was still 95 bpm and ABP was 110/60 mmHg. On physical
examination, grade 2/6 systolic murmur localized to the area of the left
sternal border and bilateral basal crackles were documented; vesicular
breath sounds were diminished. Further blood exams showed
hypoalbuminemia (15 g/l), hypoproteinemia (50 g/l) and decreased levels
of antithrombin III (<60%). Electrocardiography showed low QRS
voltage in precordial leads while echocardiography documented
hypertrophic cardiomyopathy and thickened interventricular septum. Serum
protein electrophoresis showed a band in β1 globulin region; on
immunofixation electrophoresis, serum revealed IgA lambda monoclonal
component (16 g/l) (Figure 1) . The 24-h proteinuria was 6,4 g
and Bence-Jones protein was detected in the urine. Serum IgA was higher
than normal range (12,75 g/l). Total body computed tomography (CT) scan
showed bilateral pleural effusion and small pericardial effusion (6 mm).
In the suspicion of amyloidosis, despite the negativity of the abdominal
fat pad fine-needle aspiration biopsy, myocardial scintigraphy and
magnetic resonance (MRI) were then performed. Scintigraphy (and genetic
testing) was negative for the ATTR subtype. Cardiac MRI revealed
asymmetric, non-obstructive and hypertrophic cardiomyopathy, thickened
interventricular septum (20 mm), and circumferential late gadolinium
enhancement in the sub-mesocardial area, indicating amyloid accumulation
(Figure 2 ). Finally, kidney biopsy showed Congo red positivity
on light microscopy; while immunohistochemistry for anti-lambda
antibodies was positive, confirming light-chain (AL) amyloidosis. Based
on the patient’s anamnesis, reporting unprotected sex and recurring
fever over the last few months, microbiological investigations were
performed, revealing chronic hepatitis B infection (serum HBV DNA level
of >95 million copies/ml), EBV DNA infection and HIV
infection (serum HIV RNA level of >2 million copies/ml).
Lymphocyte subpopulation analysis showed lower CD4+ (208/μL), and
CD4/CD8 ratio of 0.10. Quantiferon-TB Gold was negative.