Ease of sutureless aortic valve replacement in a patient with unexpected ochronosis: a case report.

BACKGROUND: Alkaptonuria is a rare congenital metabolic disorder characterized by homogentisic acid accumulation in body cartilage and connective tissues due to a deficient homogentisic acid dioxygenase enzyme. This disorder manifests in various clinical symptoms, including spondyloarthropathy, ocular and dermal pigmentation, genitourinary tract obstruction by ochronosis stones, and cardiovascular system involvement. Cardiac ochronosis is a rare manifestation of alkaptonuria that may present as aortic stenosis, sometimes accompanied by other cardiovascular complications. CASE PRESENTATION: We report an unexpected case of ochronosis diagnosed during cardiac surgery. Due to the fragile, thin, and atheromatous nature of the ascending aorta in patients with ochronosis, we opted for a sutureless aortic valve replacement procedure. This approach appears to be more suitable for patients with ochronosis. CONCLUSIONS: Although cardiac ochronosis is rare, surgeons should remain vigilant and consider the possibility of this condition when examining patients with aortic valve stenosis, paying close attention to the clinical manifestations of alkaptonuria.

Disc-coloration of an ochronotic cervical intervertebral disc in a patient with alkaptonuria: Case report and review of the literature.

OBJECTIVES: Alkaptonuria is a rare inborn disorder of phenylalanine and tyrosine metabolism. It is characterized by an accumulation of homogentisic acid and its oxidation products, possibly resulting into connective tissue damaging. "Ochronosis" is a main feature, which is characterized by tissue discoloration and even alkaptonuric arthropathy. Cervical spine involvement is exceptional and there is a paucity of reports on surgical interventions in these patients. We explored the literature concerning cervical spine involvement in patients with alkaptonuria. PATIENTS AND METHODS: We performed a review of the literature, in which patients with alkaptonuric degenerative changes of the cervical spine were examined. Articles were obtained from MEDLINE. Search terms included: "cervical", "alkaptonuria", "alkaptonuric changes" and "black disc". Additional studies were identified by checking reference lists. Furthermore, we present the case of a 46 year old patient with critical cervical spinal canal stenosis who underwent C6-C7 anterior cervical microdiscectomy and interbody fusion, in order to prevent myelopathic changes. CARE statement guidelines were followed. RESULTS: Peroperatively, we did not encounter any macroscopic abnormalities of the skin, muscles or ligaments. A black discoloration of the nucleus pulposus was observed. Peroperative and postoperative course was uneventful. CONCLUSION: Alkaptonuric degenerative abnormalities most commonly involve the lumbar spine, although the cervical spine can be affected in rare cases. Most frequently, the diagnosis of alkaptonuria can be made based on the clinical phenotype many years before symptoms secondary to ochronotic arthropathy develop. A retrospective diagnosis based on peroperative black discoloration of spinal structures has been described. A black discoloration of the intervertebral disc should encourage the neurosurgeon to further explore the possibility of alkaptonuria, even in the absence of a clear phenotype. Surgical results are mostly satisfactory. Further studies are required in order to better understand this pathology and its postoperative course.

Alkaptonuria.

Alkaptonuria is a rare inborn error of metabolism caused by the deficiency of homogentisate 1,2-dioxygenase activity. The consequent homogentisic acid (HGA) accumulation in body fluids and tissues leads to a multisystemic and highly debilitating disease whose main features are dark urine, ochronosis (HGA-derived pigment in collagen-rich connective tissues), and a painful and severe form of osteoarthropathy. Other clinical manifestations are extremely variable and include kidney and prostate stones, aortic stenosis, bone fractures, and tendon, ligament and/or muscle ruptures. As an autosomal recessive disorder, alkaptonuria affects men and women equally. Debilitating symptoms appear around the third decade of life, but a proper and timely diagnosis is often delayed due to their non-specific nature and a lack of knowledge among physicians. In later stages, patients' quality of life might be seriously compromised and further complicated by comorbidities. Thus, appropriate management of alkaptonuria requires a multidisciplinary approach, and periodic clinical evaluation is advised to monitor disease progression, complications and/or comorbidities, and to enable prompt intervention. Treatment options are patient-tailored and include a combination of medications, physical therapy and surgery. Current basic and clinical research focuses on improving patient management and developing innovative therapies and implementing precision medicine strategies.

Artropatia ocronótica / Ochronotic arthropathy

Os autores apresentam o relato de caso de um paciente com artropatia ocronótica. A ocronose é uma doença rara, de herança autossômica recessiva, manifestação clínica da alcaptonúria. O paciente apresenta clinicamente dor crônica lombar, fraqueza e limitação funcional dos ombros e joelhos, associada a urina de cor escura. O objetivo do tratamento ortopédico é o controle da dor e melhora das funções das articulações acometidas, realizando artroplastias quando necessário.

Alcaptonúria: a propósito de um caso / Alkaptonuria: presentation of a case

Os autores relatam um caso de alcaptonúria, doença metabólica hereditária rara, caracterizada pela ausência da enzima ácido homogentísico-oxidase. Esse defeito leva à deposiçäo do ácido homogentísico, que é produzido durante o metabolismo da fenilalanina e tirosina, em vários tecidos, como esclera, cartilagens e pele, entre outros. É enfatizado que, embora seja doença de fácil diagnóstico, freqüentemente o médico assistente näo faz o diagnóstico por näo valorizar as queixas relatadas pelo paciente