- Serum Amino Acid Profiling in Patients with Alkaptonuria Before and After Treatment with Nitisinone. [Journal Article]
- JRJIMD Rep 2018 May 13
- CONCLUSIONS: Marked hypertyrosinaemia was observed following treatment with nitisinone. Noteworthy changes were also observed in the ratio of several amino acids following treatment with nitisinone suggesting that the availability of amino acids for neurotransmitter biosynthesis and liver function may be altered following treatment with nitisinone.
- Alkaptonuria Severity Score Index Revisited: Analysing the AKUSSI and Its Subcomponent Features. [Journal Article]
- JRJIMD Rep 2018 Apr 14
- CONCLUSIONS: PCA and redundancy analysis supported the AKUSSI as a robust AKU disease severity measure, although some AKUSSI features could be removed for simplicity. For small patient populations and rare diseases, PCA and redundancy analysis together can aid validation of disease severity metrics.
- Degenerative Osteoarthritis with Multiple Joint Arthroplasties Due to Alkaptonuria, a Rare Inborn Error of Tyrosine Metabolism. [Journal Article]
- IMIsr Med Assoc J 2018; 20(4):260-261
- Fatal methemoglobinemia complicating alkaptonuria (ochronosis): a rare presentation. [Journal Article]
- FSForensic Sci Med Pathol 2018; 14(2):236-240
- A 61-year-old female died in hospital with multiple organ failure 4 weeks following presentation with acute kidney injury, hemolytic anemia and methemoglobinemia. At autopsy, brown to black discolora...
A 61-year-old female died in hospital with multiple organ failure 4 weeks following presentation with acute kidney injury, hemolytic anemia and methemoglobinemia. At autopsy, brown to black discoloration of cartilages was observed. Histology revealed brown pigmentation of the hyaline cartilage, with focal full-thickness erosion of the articular hyaline cartilage, characteristic of alkaptonuria (ochronosis). Although alkaptonuria is rarely fatal, this case illustrates a rare acute fatal complication. Accumulation of circulating homgentisic acid secondary to acute derangement of renal function is believed to have overwhelmed the endogenous antioxidant processes, resulting in hemolysis and methemoglobinemia, which were refractory to treatment. Small numbers of cases have previously been reported in the literature in patients known to suffer with the disease, all of which were preceded by acute kidney injury. Whilst the clinical diagnosis of alkaptonuria may be challenging, the autopsy findings of this rare condition are striking and this case illustrates the utility of the autopsy, albeit retrospectively, in arriving at a diagnosis. To our knowledge this is the first reported case where previously undiagnosed alkaptonuria has presented with methemoglobinemia.
- Surgical Management in Cervical Spondylotic Myelopathy Due to Alkaptonuria. [Case Reports]
- WNWorld Neurosurg 2018; 113:308-311
- CONCLUSIONS: Ochronotic cervical spondylotic myelopathy is a rare condition and may require additional considerations in surgical treatment compared to more common causes of cervical spondylotic myelopathy. In our case, we elected for decompression with posterior occipitocervical screw fixation and were able to achieve neurologic recovery with no complications, currently at 2-year follow-up.
- Ochronosis of Mitral Valve and Coronary Arteries. [Journal Article]
- ATAnn Thorac Surg 2018 Mar 01
- Cardiac ochronosis is a rare complication of alkaptonuria, a disorder of tyrosine metabolism characterized by a triad of dark urine, pigmentation of tissues, and ochronotic arthropathies. When presen...
Cardiac ochronosis is a rare complication of alkaptonuria, a disorder of tyrosine metabolism characterized by a triad of dark urine, pigmentation of tissues, and ochronotic arthropathies. When present, cardiac ochronosis generally affects the aortic valve resulting in aortic stenosis. More rarely, it may affect the mitral valve and the coronary arteries. We describe the case of a 67-year-old lady with a history of alkaptonuria with severe ochronosis of the coronary arteries and mitral valve, requiring coronary bypass and mitral valve replacement.
- Reduction of frontal plane knee load caused by lateral trunk lean depends on step width. [Journal Article]
- GPGait Posture 2018; 61:483-487
- The internal knee abduction moment (KAM) in osteoarthritis is reduced by increased lateral trunk lean (TL). Mechanistically, this occurs as the Centre of Mass (COM) moves further over the stance leg....
The internal knee abduction moment (KAM) in osteoarthritis is reduced by increased lateral trunk lean (TL). Mechanistically, this occurs as the Centre of Mass (COM) moves further over the stance leg. Since the size of the base of support constrains the COM, an associated increase in step width (SW) would be expected to maintain stability. This study tested the effects of TL on SW and KAM in healthy participants (n = 21) who performed normal and 6° TL walks. The latter was controlled via audio-visual biofeedback. We found two distinct gait strategies in TL walk: widening the step width substantially (>50%) to permit an increase in the COM displacement (WSW, n = 13), or maintaining a baseline SW and minimally displacing the COM by moving the hip/pelvic complex in the opposite direction (NSW, n = 8). WSW doubled SW (11.3 ± 2.4 v. 24.7 ± 5.5 cm, p < .0001), NSW did not change SW (12.2 ± 2.8 v. 13.7 ± 4.7 cm, p > .05). These two distinct gait strategies resulted in unique patterns of KAM reduction across the stance phase. NSW reduced KAM impulse significantly in the initial half (0.08 ± 0.02 v. 0.06 ± 0.02, p = .04) but not in the later stance phase (0.07 ± 0.02 v. 0.07 ± 0.04, p > .05). WSW reduced KAM significantly in both initial (0.11 ± 0.03 v. 0.08 ± 0.04, p < .001) and later stance phase (0.09 ± 0.02 v. 0.06 ± 0.03, p < .001). KAM peak results followed the pattern of impulse. This study has revealed two distinct mechanisms for increasing lateral trunk lean which can be used to explain discrepancies in past research and in the future could be used to individualise gait re-training strategies.
- Determination of homogentisic acid in urine for diagnosis of alcaptonuria: Capillary electrophoretic method optimization using experimental design. [Journal Article]
- BCBiomed Chromatogr 2018 Feb 20; :e4216
- Homogentisic acid (HGA) is a diagnostic metabolite that accumulates in the urine and tissues of patients with alkaptonuria which is a rare autosomal recessive disease. HGA is a specific metabolite in...
Homogentisic acid (HGA) is a diagnostic metabolite that accumulates in the urine and tissues of patients with alkaptonuria which is a rare autosomal recessive disease. HGA is a specific metabolite in urine and serum, which is used for diagnosis of alkaptonuria. This study presents an inexpensive and easy capillary electrophoretic method for the quantitative determination of HGA in urine samples. The method was optimized using full factorial experimental design. The optimal separation electrolyte and separation voltage were revealed as 45 mmol/L phosphate buffer at pH 7.0 and 22 kV, respectively. Under these conditions the presence of HGA was detected in 6 min. Repeatability of migration times and corrected peak areas of HGA (as RSD) were 0.37 and 1.99, respectively. The detection limit was 0.56 μg/mL, 3 times of the average noise, and the quantification limit was 1.85 μg/mL, 10 times the average noise for HGA. Urine samples were directly injected to the capillary without any pretreatment step.
- How to Measure Tissue Oxygenation Using Near-Infrared Spectroscopy in a Patient With Alkaptonuria. [Journal Article]
- JCJ Cardiothorac Vasc Anesth 2018 Jan 31
New Search Next
- Alkaptonuric Ochronosis and the Failure of Regional Cerebral Tissue Oxygen Saturation Monitoring by Two Different Near-infrared Spectroscopy Devices. [Journal Article]
- JCJ Cardiothorac Vasc Anesth 2017 Dec 29