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European Journal of Rheumatology Sep 2018Exogenous ochronosis is characterized by hyperpigmented skin lesions that arise in association with local suppression of homogentisic acid oxidase enzyme. Although it...
Exogenous ochronosis is characterized by hyperpigmented skin lesions that arise in association with local suppression of homogentisic acid oxidase enzyme. Although it generally develops in association with topical application of chemical agents, it can occasionally develop in association with antimalarial drugs. Here we present the case of a patient with rheumatoid arthritis who developed hyperpigmentation on the face and neck regions during hydroxychloroquine treatment. Hydroxychloroquine is being widely used in rheumatology practice, and cutaneous hyperpigmentation may develop as an adverse effect. In the present case, we emphasize the potential underlying mechanisms through which it may cause cutaneous hyperpigmentation and determine the clinical and histopathological findings of exogenous ochronosis.
PubMed: 30071940
DOI: 10.5152/eurjrheum.2018.17190 -
Turk Gogus Kalp Damar Cerrahisi Dergisi Jan 2022Alkaptonuria is a rare inherited metabolic disease caused by homogentisic acid oxidase enzyme deficiency. Homogentisic acid formed during phenylalanine and tyrosine...
Alkaptonuria is a rare inherited metabolic disease caused by homogentisic acid oxidase enzyme deficiency. Homogentisic acid formed during phenylalanine and tyrosine metabolism cannot be further metabolized and accumulates due to this enzyme deficiency. Some of the homogentisic acid that cannot be removed by metabolism is excreted with urine, some of it causes this accumulation known as ochronosis, which is characterized by dark pigmented color change in tissues. The classic clinical triad of the disease is darkening of the urine color, degenerative arthritis in the joints and dark colored pigmentation in the connective tissue. Herein, we present a case of ochronosis detected incidentally during aortic valve replacement with the diagnosis of aortic insufficiency.
PubMed: 35444851
DOI: 10.5606/tgkdc.dergisi.2022.20909 -
Journal of Orthopaedic Case Reports Jul 2021Ochronotic arthropathy in patients with alkaptonuria is a rare hereditary disorder. The altered metabolism causes the homogentesic acid derivatives to deposit in various...
INTRODUCTION
Ochronotic arthropathy in patients with alkaptonuria is a rare hereditary disorder. The altered metabolism causes the homogentesic acid derivatives to deposit in various connective tissues causing characteristic pigmentation. Due to the close clinical resemblance to that of a degenerative disorder, diagnosis of ochronotic arthropathy usually occurs intraoperatively. We report arthroscopic findings of a 50-year-old female with ochronotic arthropathy.
CASE REPORT
A 50-year-old woman came with complaints of pain and swelling in the left knee. Clinical examination and MRI findings were correlated to reveal a tear of lateral meniscus. On arthroscopic examination, the blackish pigmentation of the meniscus and the articular cartilage led to the diagnosis of ochronotic arthropathy.
CONCLUSION
Arthroscopy plays an important role in diagnosis and treatment of patients with ochronotic arthropathy. The characteristic arthroscopic finding may aid diagnosis even in patients who do not have other systemic manifestations. Timely arthroscopic intervention can help delay the disease progression.
PubMed: 34790614
DOI: 10.13107/jocr.2021.v11.i07.2334 -
Journal of Cutaneous and Aesthetic... 2024Facial pigmentation is a common presentation of patients attending dermatology out patient department (OPD) and is of great concern to patients. Facial pigmentation may...
INTRODUCTION
Facial pigmentation is a common presentation of patients attending dermatology out patient department (OPD) and is of great concern to patients. Facial pigmentation may be multifactorial and is only rarely diagnosed accurately by a detailed history and clinical examination. Pigmentary disorders cause psychological distress and negatively impact the quality of life of an individual.
AIMS AND OBJECTIVES
(1) To study different dermoscopic patterns in facial melanosis. (2) To estimate the frequency of different dermoscopic patterns.
MATERIALS AND METHODS
Patients with facial hyperpigmentation attending the dermatology OPD were recruited after taking their written consent. A detailed history was taken to collect demographic data. Clinical examination and dermoscopy were done in all patients. Biopsy was done as and when required. Descriptive statistics has been used to describe the quantitative data. Qualitative data were presented as frequency and percentage for clinical and dermoscopic patterns.
RESULTS
The study included 100 patients with 15 different facial melanoses. The most common age group affected was 21-40 years in 53 (53%) cases. The female-to-male ratio was 1.63:1. Melasma was reported as the most common cause of facial melanosis constituting 49 (49%) of the total cases. Out of the total melasma cases, epidermal melasma constituted 22 (45%) cases, dermal melasma constituted four (4%) cases and mixed melasma constituted 23 (47%) cases. Other cases included were lichen planus pigmentosus (14; 14%), facial acanthosis nigricans (14; 14%), periorbital hyperpigmentation (7; 7%), post-inflammatory hyperpigmentation (4; 4%), exogenous ochronosis (2; 2%), lentigines (2; 2%), frictional melanosis (2;2%), and one case each of Becker's nevus, nevus of Ota, olanzapine-induced hyperpigmentation, Riehl's melanosis, macular amyloidosis, and tanning.
CONCLUSIONS
Melasma was reported as the most common cause of facial melanosis. The most common dermoscopic feature was accentuated pseudopigment network. The study is beneficial in understanding the different clinical and dermoscopic patterns of facial melanosis, thus helping the physician to effectively manage the conditions and reduce the need of biopsy.
LIMITATIONS
(1) A small sample size. (2) Histopathological correlation was not done in all cases.
PubMed: 38800811
DOI: 10.4103/JCAS.JCAS_48_23 -
BioMed Research International 2021Metabolic disorder alkaptonuria is an autosomal recessive disorder caused by mutations in the gene, and a deficiency HGD enzyme activity results in an accumulation of...
BACKGROUND
Metabolic disorder alkaptonuria is an autosomal recessive disorder caused by mutations in the gene, and a deficiency HGD enzyme activity results in an accumulation of homogentisic acid (HGA), ochronosis, and destruction of connective tissue.
METHODS
We clinically evaluated 18 alkaptonuria patients (age range, 3 to 60 years) from four unrelated families. Furthermore, 11 out of 18 alkaptonuria patients and 7 unaffected members were enrolled for molecular investigations by utilizing Sanger sequencing to identify variants of the 14 exons of gene.
RESULTS
We found that the seven patients from the 4 unrelated families carried a recurrent pathogenic missense variant (c.365C>T, p. Ala122Val) in exon 6 of gene. The variant was fully segregated with the disease in affected family members while the other unaffected family members were heterozygous carriers for this variant. Additionally, the clinical features were fully predicted with alkaptonuria disorder.
CONCLUSION
In this study, we confirmed that the most common variants in Jordanian AKU patients was c.365C>T, p. Ala122Val in exon 6 of gene. Additionally, we correlated the clinical and genetic features of AKU patients at various ages (3-60 years).
Topics: Adolescent; Adult; Alkaptonuria; Child; Child, Preschool; Exons; Family Health; Female; Founder Effect; Genes, Recessive; Genetic Variation; Heterozygote; Homogentisate 1,2-Dioxygenase; Homogentisic Acid; Humans; Jordan; Male; Middle Aged; Mutation, Missense; Ochronosis; Oligonucleotides; Pedigree; Sequence Analysis, DNA; Young Adult
PubMed: 34235214
DOI: 10.1155/2021/1515641 -
Journal of Neurosciences in Rural... 2015Alkaptonuria (AKU) is considered a rare autosomal recessive condition that results in an accumulation of homogentisic acid in body tissues and causes long-term clinical,...
Alkaptonuria (AKU) is considered a rare autosomal recessive condition that results in an accumulation of homogentisic acid in body tissues and causes long-term clinical, neurological and psychological complications. We present a comprehensive evaluation of an atypical 46-year-old Caucasian male who developed all clinical diagnostic symptoms of AKU (ochronotic pigmentations, dark urine and clinical arthritis of major joints including spine) by 25 years of age, well before the typical age mentioned in many reviews. First signs of ochronotic ear pigmentations unexpectedly started appearing as early as 12 years of age. A long "disease-free" period typical in classical AKU patient was also absent. This case report highlights the importance of considering psychological issues in AKU patients. The patient showed symptoms of dysthymia reporting social isolation, diminished interest in pleasurable activities, feeling of worthlessness and irritability as major psychological issues. Early ochronotic pigmentation, advanced spinal myelopathy and arthropathy of major joints suggests aggressive course of the disease. Our patient underwent bilateral shoulder replacement due to AKU-induced arthropathy resulting in restoration of some range of motions. AKU is not fully understood and we recommend treating it as a multidimensional disease with simultaneous physiological, neurological and psychological effects. Early diagnosis, understanding of disease prognosis and emphasis on psychological health is needed to improve the quality of life of AKU patients.
PubMed: 25883496
DOI: 10.4103/0976-3147.150312 -
Revista Espanola de Cirugia Ortopedica... 2021Ochronosis is a rare genetic disease of phenylamine and tyrosine metabolism in which an accumulation of homogentisic acid occurs. The accumulation of HGA causes...
Ochronosis is a rare genetic disease of phenylamine and tyrosine metabolism in which an accumulation of homogentisic acid occurs. The accumulation of HGA causes alkaptonuria and deposition in the connective tissue causing a dark colouring of the tissue. In the joints, it can lead to early and very disabling arthropathy, known as ochronotic arthropathy. We present the case of a patient diagnosed with ochronosis and ochronotic arthropathy of the left knee, in which we describe the intraoperative process with the macroscopic and microscopic anatomopathological findings. The patient made good progress after implantation of a total knee prosthesis (TKP), PS type, and was able to follow the same rehabilitation protocol used in patients without ochronotic arthropathy undergoing TKP. The patient showed improvement in the different functional scales, as well as disappearance of pain.
PubMed: 32192929
DOI: 10.1016/j.recot.2020.01.005 -
Arthroplasty Today Dec 2020Alkaptonuria is a rare autosomal recessive metabolic disorder. It is characterized by the accumulation of homogentisic acid in the body due to a lack of enzymes that...
Alkaptonuria is a rare autosomal recessive metabolic disorder. It is characterized by the accumulation of homogentisic acid in the body due to a lack of enzymes that degrade it. Over time, it results in joint degeneration and eventually leads to ochronosis. Ochronosis refers to bluish-black discoloration of connective and other tissues within the body. In this study, we present 5 distinct cases diagnosed with alkaptonuria. They have undergone 8 total joint replacement surgeries (4 hips and 4 knees) within 8 years (2010-2018). All patients had an excellent outcome over several years. The follow-up period ranged from 2 to 10 years. Although none of the presented cases had intraoperative or postoperative adverse sequelae, we must take care when dealing with patients with ochronotic arthropathy. They carry a higher risk of complications than other patients with osteoarthritis disease. These complications include fractures due to fragile bone quality, muscle or tendon rupture, joint instability, and anesthesia-related complications. Total joint arthroplasty is a valid and safe option in the management of hip and knee ochronotic arthropathy.
PubMed: 32875021
DOI: 10.1016/j.artd.2020.07.037 -
NPJ Genomic Medicine Oct 2021Alkaptonuria is a rare autosomal recessive inherited disorder of tyrosine metabolism, which causes ochronosis, arthropathy, cardiac valvular calcification, and...
Alkaptonuria is a rare autosomal recessive inherited disorder of tyrosine metabolism, which causes ochronosis, arthropathy, cardiac valvular calcification, and urolithiasis. The epidemiology of alkaptonuria in East Asia is not clear. In this study, patients diagnosed with alkaptonuria from January 2010 to June 2020 were reviewed. Their clinical and molecular features were further compared with those of patients from other countries. Three patients were found to have alkaptonuria. Mutation analyses of the homogentisate 1,2-dioxygenase gene (HGD) showed four novel variants c.16-2063 A > C, p.(Thr196Ile), p.(Gly344AspfsTer25), and p.(Gly362Arg) in six mutated alleles (83.3%). RNA sequencing revealed that c.16-2063 A > C activates a cryptic exon, causing protein truncation p.(Tyr5_Ile6insValTer17). A literature search identified another 6 patients with alkaptonuria in East Asia; including our cases, 13 of the 18 mutated alleles have not been reported elsewhere in the world. Alkaptonuria is rare in Taiwan and East Asia, with HGD variants being mostly novel and private.
PubMed: 34686677
DOI: 10.1038/s41525-021-00252-2 -
Molecules (Basel, Switzerland) Mar 2023Alkaptonuria (AKU) is a rare genetic autosomal recessive disorder characterized by elevated serum levels of homogentisic acid (HGA). In this disease, tyrosine metabolism...
Alkaptonuria (AKU) is a rare genetic autosomal recessive disorder characterized by elevated serum levels of homogentisic acid (HGA). In this disease, tyrosine metabolism is interrupted because of the alterations in homogentisate dioxygenase (HGD) gene. The patient suffers from ochronosis, fractures, and tendon ruptures. To date, no medicine has been approved for the treatment of AKU. However, physiotherapy and strong painkillers are administered to help mitigate the condition. Recently, nitisinone, an FDA-approved drug for type 1 tyrosinemia, has been given to AKU patients in some countries and has shown encouraging results in reducing the disease progression. However, this drug is not the targeted treatment for AKU, and causes keratopathy. Therefore, the foremost aim of this study is the identification of potent and druggable inhibitors of AKU with no or minimal side effects by targeting 4-hydroxyphenylpyruvate dioxygenase. To achieve our goal, we have performed computational modelling using BioSolveIT suit. The library of ligands for molecular docking was acquired by fragment replacement of reference molecules by ReCore. Subsequently, the hits were screened on the basis of estimated affinities, and their pharmacokinetic properties were evaluated using SwissADME. Afterward, the interactions between target and ligands were investigated using Discovery Studio. Ultimately, compounds and were identified as potent inhibitors of 4-hydroxyphenylpyruvate dioxygenase.
Topics: Humans; Alkaptonuria; 4-Hydroxyphenylpyruvate Dioxygenase; Molecular Docking Simulation; Ochronosis; Homogentisic Acid
PubMed: 36985595
DOI: 10.3390/molecules28062623