A 40-year-old male presented to the emergency department with edema.
She has a family history of a mother with renal amyloidosis unrelated.
The report of the mother's renal biopsy reports resistance to permanganate, which seems to rule out AA amyloidosis, and leads us to consider, at the time of diagnosis, the possibility of AL amyloidosis.
The patient did not receive any pharmacological treatment.
Physical examination revealed a blood pressure of 135/75 mmHg and bimale edema without other relevant data.
Laboratory tests confirmed the presence of nephrotic syndrome (serum albumin of 2.5 g/dl, cholesterol of 275 mg/dl and proteinuria of 6 g/24 h), with no changes in the sediment and normal glomerular sclerosis.
Electrophoretic spectrum in blood and urine, immunological study and renal ultrasound are normal.
Biopsy renal outcome shows significant glomeruli with a completely distorted structure due to a hyaline deposit nodular arrangement, with positivity for Congo and timilosis in red vessels; tubules are compatible and not with thymylosis.
The paraffin-embedded sample showed marked positivity for AP protein, which is part of the amyloid substance common in all types of amyloidosis, with negativity for light chains and AA proteins.
Fibrinolysis with antibodies against fibrinogen and lysozyme is performed, resulting in amyloid substance deposits positive for A alpha chain of fibrinogen (Afib).
However, in the genetic study no mutation was found in the Afib chain gene, and a previously undescribed mutation in the apolipoprotein AI gene (apo AI) was demonstrated.
This discrepancy is analyzed by biopsy of the mother, which contains glomerular deposit in the cortex and massive deposit at the medullary level.
Medullary deposit is not described in amyloidosis Afib, being very characteristic of apo AI.
We conclude that the first results of immunohistochemistry are unreliable because it has not been done under appropriate conditions, and the presence of apoA-I was confirmed by the same technique.
An extension study was performed with echocardiography and electromyography, with no evidence of cardiac involvement or autonomic neuropathy.
A progressive increase in transaminase levels suggestive of liver involvement was detected.
These results are consistent with this type of familial amyloidosis, with preferential renal and hepatic involvement.
Despite initial normality, renal function deteriorates progressively until renal replacement therapy is required within 2 years.
The patient was treated with peritoneal dialysis for 4 years, until surgery was performed with renal transplantation from a cadaver donor.
It presents a complicated post-operative period with splenic rupture, in the context of the disease, with amyloid deposits in the spleen, requiring urgent resection.
Finally, the patient is discharged in a stable situation.
