Mineral-bone disorders and extra-bone calcification in a patient on maintenance hemodialysis

Introduction Mineral-bone disorders (MBD) and extra-bone calcification (EBC) are common and clinically significant complications in patients undergoing maintenance hemodialysis (MH) [1]. Radiological methods of visualization and echocardiography play a key role in the diagnosis of the effects of MBD and EBC outcomes [2, 3]. Case presentation Young male patient was admitted to our hospital for treatment of rough MBD and EBC due to severe tertiary hyperparathyroidism. Proteinuria was detected for the first time at the age of 14. Nephrotic syndrome was diagnosed and glucocorticosteroid (GCS) therapy was initiated. Nephrobiopsy was performed at the age of 16, but it turned on to be inconclusive and did not allow to verify the nature of kidney disease. However, the GSC therapy was continued. Over the next 10 years the patient was lost for follow-up. He sought for medical aid only at the stage of dialysis-required renal failure. Fig. 1A shows axial CT (slice at the level of the renal arteries) without contrast enhancement with widespread calcification of the small vessels in the shrunken native kidneys and calcification of the intestinal branches of the upper mesenteric artery. Fig. 1B is performed in the mode of CT volume rendering (CT VR) without contrast enhancement and demonstrates the possibility of visualizing the contours of the kidneys with massive calcification of parenchymal renal vessels. In In Fig. 1C calcified intestinal branches of the superior mesenteric artery are visible, including its terminal arched branch (ileo-colonic artery), and the calcified inferior mesenteric artery with its branches are well visible. It should be noted that the inferior artery segment is extremely difficult to visualize even when contrast-enhanced. EBC is also known as medial calcific sclerosis, is characterised by calcific deposits within the media of medium and small muscular arteries that do not cause luminal narrowing, unlike atherosclerotic deposits are located on the wall of a large and medium-sized arteries [4]. Fig. 2A shows the computed tomography finding of the patient's spine: the signs of the "Rugger Jersey spine” describes the prominent endplate densities at multiple contiguous vertebral levels to produce an alternating sclerotic-lucent-sclerotic appearance. This mimics the horizontal stripes of a rugby jersey. This term and pattern are distinctive for renal osteodystrophy [5]. On the radiograph of the wrists ( Fig. 2B) acro-osteolysis of the distal phalanges of the 1st, 2nd, 3rd fingers on both sides is determined, initial acro-osteolysis of the distal phalanges of the 4th and 5th fingers of the right hand and the 5th finger of the left hand, pronounced compaction and an increase in the volume of the soft tissues of the 1st, 2nd, 3rd fingers of the distal phalanges by the type of finger clubbing also called "drumsticks", (arrows). The cause of distal osteolysis and the formation of "drumsticks" is a trophic disorder caused by calcification of the vessels of the hands. Fig. 2B ZOOM shows the the signs of subperiosteal resorption of the radial surface of the middle phalanx of the 3rd finger of the right hand (arrow). Similar changes are observed in the patient’s 2nd and 3rd fingers of both hands and are considered characteristic of any variants of hyperparathyroidism [5]. Echocardiographic (Echo) findings are presented at Fig. 2C (apical 4-Chamber). The arrow indicates massive calcification of the fibrous annulus and mitral valve leaflets. Inclusions of calcium in the structure of the myocardium and chordal apparatus of the mitral valve are also visible. These changes caused the formation of severe mitral valve disease. The clinical consequences of severe MBD and EBC are heart failure, disorders of peripheral blood circulation and physical disability. Conclusion The presented clinical case demonstrates underestimated and neglected MBD and EBC in the young patient on MH due to unspecified nephropathy. Radiological and Echo diagnostic approaches allow to assess the prevalence of these lesions and to control the efficiency of the applied medical strategies. The Informed Consent for the publication of the personal data and images was obtained from the patient. The authors declare no conflict of interest.

минерально-костные нарушения, ренальная остеодистрофия, акро-остеолизис, гиперпаратиреоз, сосудистая кальцификация, клиническое наблюдение, mineral bone disorder, renal osteodystrophy, acro-osteolysis, hyperparathyroidism, vascular calcification, case report

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