Case report.
Clinical history: He suffered from hypertension, well
controlled with medical therapy
Case presentation: In the April 2020 a 57 years Caucasian
old man was referred to our Hematologic Center by a nephrologist for
anemia, renal failure, hypercalcemia and bone lesions with the suspicion
of MM. The past medical history of patient reported fatigue, night
swears and weight loss from January 2018. In the February 2018 it is
documented a mild and progressive hypochromic-normocytic nemia (Hb 10,6
gr/dl) with hyperferritinemia, low iron blood levels and low count of
reticulocytes. A colonoscopy showed two intestinal polyps with a high
grade dysplasia. In the December 2019 it was performed a radiography of
lumbar spine because of onset of pain with the finding of multiple lytic
lesions. From January 2020 the patient was followed with blood tests
with the documentation of a progressive anemia (Hgb 8,5 gr/dl), renal
failure (serum creatinine 1,57 mg/dl, glomerular filtration 43 ml/min
according to Modification of diet in renal disease (MDRD ), glycosuria
(with normal value of glycemia and glycated hemoglobin). He was referred
to Nephrology Center for a comprehensive evaluation. It was confirmed
the anemia and renal failure with a slight glomerular proteinuria (0,95
gr/24 hour). Blood tests showed hypercalcemia (serum calcium 12,9
mg/dl), normal serum albumin. A skeletal survey and total body CT
confirmed the multiple bone lysis interesting the whole skeleton and
particularly the pelvis, bilateral femurs, dorsal vertebrae with erosion
of the bone cortical. Notably it was described a lesion of the left lobe
of the thyroid gland.
Initial work-up: In the first hematological examination
the patient complained fatigue and diffuse skeletal pain. There were not
remarkable clinical signs. The blood test confirmed the mild
normocytic-normochromic anemia, hypercalcemia, high levels of serum
calcium and a mild renal failure. We performed investigation focused on
definition of MM diagnosis . But, no monoclonal component was detected
by serum and urine protein electrophoresis, serum and urine
immunofixation. The levels of serum immunoglobulins and free light
chains were normal according with renal function. Bone marrow biopsy and
aspirate did not show a monoclonal plasma cell infiltrate. The patient
underwent treatment with fluid hydration and Zoledronic acid to correct
(with a reduction of dosage according with glomerular filtrate).
Differential diagnosis: After excluding a monoclonal
gammopathy our attempts were aimed to discover other neoplastic or
endocrine diseases that could cause the clinical manifestations of our
patient.
Further examination: A FDG PET-TC was performed to rule
out further pathologic finding. This evaluation showed a diffuse
hypercaptation of bone marrow and different bone sites, particularly the
jaw, bilateral ribs, dorsal and lumbar vertebral vertebrae, pelvis and
bilateral femurs. A CT-guided biopsy of the third dorsal vertebra was
performed: the histologic examination was coherent with a “brown
tumor” (fig.1a, 1b,1c).