Publications

The mucopolysaccharidoses (MPS) are a common cause of carpal tunnel syndrome (CTS) in children and adolescents. As the MPS diseases are progressive in nature, it is essential that CTS in these children is readily diagnosed and treated, before damage to the median nerve becomes irreversible. Currently, no standards for diagnosing and treating CTS associated with MPS exist. Proper diagnosis of CTS generally involves the assessment of clinical signs and symptoms, in combination with nerve conduction studies. As the clinical signs and symptoms of CTS described for adults are often absent in children with MPS, early diagnosis of CTS in these children requires recognition of subtle findings such as decreased sweating, nocturnal waking, gnawing of hands, and manual clumsiness. Sensory tests could also be useful for detecting early CTS when the integrity of the nerve is still relatively intact. Nerve conduction velocities, which are the gold standard for diagnosing CTS, can be difficult to perform in patients with MPS and should be adapted to the patients' clinical characteristics such as their abnormally small hands and young age. Ongoing monitoring for CTS is indicated for all MPS patients, including those treated with hematopoietic stem cell transplantation or enzyme replacement therapy.

Enzyme replacement therapy has been successful in alleviating morbidity and improving endurance in Mucopolysaccharidosis (MPS) type I, II, and VI, however little attention has been paid to the effects on bone mineralization. Brief case reports in MPS type III and IV suggest that bone mineral density (BMD) is diminished, but did not account for patient size. In this report, BMD was evaluated by quantitative computed tomography and by dual-energy x-ray absorptiometry (DXA) in separate studies involving 10 patients with MPS type VI (7 Female; 7.0 to 21.0 y) and 4 male patients with MPS II (8.1 to 35.5 y). Vitamin D intake met the current RDA (200 IU) for most, though 25-OH vitamin D was insufficient (< 30 ng/mL) in 87.5% of patients tested. Ht Z-score was low -5.8 +/- 3.6, with height deficits greatest in MPS VI. Spine and whole body BMD Z-scores by DXA were considered normal for chronological age in all MPS II, and after correction for Ht Z-score, in all but one subject with MPS VI. These results suggest that vitamin D insufficiency is quite common in MPS. BMD by DXA is within normal range for most, particularly after correction for short stature. A review of bone health assessment is provided as well as a discussion of these results.

With improved survival afforded by highly active antiretroviral therapy (HAART), CKD has emerged as one of the primary comorbid conditions affecting HIV-infected individuals. Although CKD in HIV-infected individuals is classically thought of as a consequence of advanced HIV infection such as in the case of HIV-associated nephropathy, several factors likely contribute to the development CKD in HIV infection. These factors include genetic predisposition, age-related decline in kidney function, HAART-related metabolic changes, exposure to multiple nephrotoxic medications, and concurrent conditions such as hepatitis C or illicit drug use. Similar to the general population, proteinuria and impaired kidney function are associated with faster progression to acquired immune deficiency syndrome and death. Given the prevalence and impact of kidney disease on the course of HIV infection and its management, current guidelines recommend screening all HIV-infected individuals for kidney disease. This review focuses on the current guidelines for kidney disease screening and discusses traditional as well as promising strategies for detecting CKD in this vulnerable population.