A 33-year-old man consulted with Nephrology at the end of 2006 for elevated serum creatinine (Crs) to 1.4 mg/dl. He did not report any history or clinical manifestations of urological or renal disease.
Five years before, Crs was 0.9 mg/dl.
Anemia due to iron deficiency and gastroesophageal reflux was diagnosed at 18 years of age.
In the last 4 years he reported dysphagia and postprandial heaviness, without other gastrointestinal manifestations, as well as mechanical lumbar pain.
Absence of febrile episodes, joint inflammation, skin lesions, serositis, or other organs or systems
Family history of ankylopoietic spondylitis in several men of the paternal branch; a paternal uncle was also diagnosed with stage 5 chronic kidney disease secondary to nephropathy due to analgesic abuse.
Physical examination normal, blood pressure 130/79 mmHg, body mass index 21 kg/m2.
Investigations
Blood analysis: 1.47 mg/dl; estimated glomerular filtration rate (eGFR) by MDRD-4: 59 ml/min/1.73 m2; lipids: 33 mg/dl; normal hepatic enzymes and urea.
Total proteins, proteinogram, immunoglobulins and complement: normal.
Rheumatoid factor was negative.
C-reactive protein (CRP): 13 mg/l (normal value [VN] < 10 mg/l).
Antinuclear antibodies, anti-DNA antibodies, anti-neutrophil cytoplasmic antibodies and histocompatibility antigen-B27 were negative.
Ferric parameters: sideremia: 25 μg/dl (VN: 40-60); ferritin: 38 ng/ml (VN: 20-300), transferrin saturation index: 12%.
Vitamin B12: 181 pg/ml (VN: 208-930) and folic acid: 3.3 ng/ml (VN: 7.2-15).
Urine analysis: proteinuria: 200 mg/24 h; albuminuria: 47 mg/24 h, without monoclonal free light chains.
Urinalysis was normal.
Chest and spine radiographs showed no significant changes.
Abdominal, renal and urinary tract ultrasound: normal.
Assessed by the Rheumatology Department, ankylopoietic spondylitis was ruled out.
Blood tests at 2 months showed: Crs: 1.64 mg/dl; eGFR (MDRD-4): 52 ml/min/1.73 m2; proteinuria: 316 mg/24 h; albuminuria: 163 mg/24 h.
And 4 months later: Crs: 1.77 mg/dl; eGFR (MDRD-4): 47 ml/min/1.73 m2; proteinuria: 640 mg/24 h.
Iron and vitamin B12 deficiencies were partially corrected with oral supplements.
Persistence of gastrointestinal symptoms (dysphagia, dyspepsia) and suspicion of intestinal malabsorption (iron and vitamin deficiencies), we propose an endoscopic study of the digestive tract with biopsies.
The main alterations were found at the level of the mucosa of the terminal ileum: ulcerated villous, inflammatory lymphoplasmacytic reaction in lamina propria, with neutrophil architecture (abscesses granulomatous CD)
In the mucosa of the rectum, on the walls of the blood vessels of the lamina propria, a deposit of material with tintorial characteristics (congo red and immunohistochemical) typical of AA amyloidosis was found.
Percutaneous renal biopsy was also performed due to the unfavorable progression of the parameters (renal function and proteinuria), which showed: 7 glomeruli, 3 interstitial walls and eosinophilic deposits in the blood vessels and the remaining glomerular material deposits scarce
The deposits were congo red positive with green birefringence in polarized light and immunohistochemistry determined the presence of amyloid A protein.
This patient had no symptoms or clinical signs suggestive of another type of inflammatory, infectious or tumoral disease or familial Mediterranean fever in the subsequent evolution.
With the diagnosis of CD and secondary amyloidosis AA it was decided an etiological treatment of CD based on infliximab 5 mg/kg intravenously every 2 months, azathioprine leukoprina 1-1.5 mg/kg/day (
Renal parameters improved, as well as inflammatory markers (CRP: 5 mg/l, and serum amyloid A protein < 5 mg/l), and were maintained after 4 years of follow-up.
There were no major complications of CS or side effects of medication.
