Respiratory muscular strength in children with mucopolysacaridosis: comparison with predictive equations.

BACKGROUND: Mucopolysaccharidoses (MPS) are rare metabolic diseases that impair respiratory function leading to respiratory failure. This study aimed to compare maximal inspiratory and expiratory pressures (MIP and MEP) obtained in children with MPS and compare with predicted values from previous studies involving healthy children. METHODS: This is a cross-sectional study, in which the chest deformity was evaluated; MIP, MEP through digital manometer, and lung function through spirometry. MIP and MEP were compared with five different predict equations and with a control group of healthy children. Agreement between respiratory muscle weakness regarding absolute values of MIP and MEP in relation to predictive values by the equations included in the study were assessed by Kappa coefficient. RESULTS: MPS group was composed of 22 subjects. 45.5% had pectus carinatum, 36.4% pectus excavatum, and presented lower MIP (37.14±36.23 cmH2O) and MEP (60.09±22.3 cmH2O) compared with control group (22 healthy subjects) (MIP: 91.45±35.60; MEP: 95.73±22.38). Only the MEP equations proposed by Tomalak et al. were close to those found in our MPS children (P=0.09). In the MPS group it was observed a weak agreement between inspiratory weakness through absolute and predicted values in only two equations: Tomalak et al. and Domenèch-Clar et al. (for both: k=0.35, P value =0.03); and for MEP a moderate agreement was found using all predictive equations. CONCLUSIONS: In MPS children MRP data should not be normalized using the reference equations for healthy ones, is more coherent to longitudinally follow absolute pressures and lung volumes in this group.

Functioning profiles of individuals with Mucopolysaccharidosis according to the International Classification of Functioning.

BACKGROUND: The classification of health problems of persons with Mucopolysaccharidosis (MPS) based on the International Classification of Functioning, Disability and Health (ICF) may contribute to better understanding the disease impacts. The ICF is a useful tool to describe disabilities and functioning, especially in diseases with multisystemic involvement. AIM: To identify and classify the health needs of persons with non-neuronopathic MPS according to the ICF. DESIGN: A cross-sectional study. SETTING: Department of Physical Therapy (Federal University, Brazil). POPULATION: Persons with non-neuronopathic MPS. METHODS: Semi-structured interviews covering all components of the ICF were conducted to know the patients' perspectives of their health problems (patient-reported outcomes). The speeches were transcribed verbatim and analyzed by researchers to identifying meaningful concepts. Then, the concept units were linked to ICF components and the magnitude of the problem to ICF qualifiers. Data are shown by descriptive statistics and separated into two groups: children and adolescents, and adults. RESULTS: A total of 60 different ICF categories were used to classify participants' functioning. A total of 28 and 51 categories was necessary to classify the health problems of children and adults, respectively. Additionally, 16 categories related to contextual factors were used, of which eight and 12 were identified as facilitators by children, adolescents, and adults, respectively. The main problems were related to supportive functioning of arms or legs (b7603), pain in the body part (b2801), respiratory functions (b440), and voice functions (b310). Limitations in the activity and participation component were related to walking (d450), fine hand use (d440), washing oneself (d510), and dressing (d540). Recreation and leisure (d920) was restricted to approximately half of the studied population. CONCLUSIONS: People with MPS face impairments of body structures and functions, activity limitations and restrictions to participation. Environmental factors may be act as facilitators of these problems. CLINICAL REHABILITATION IMPACT: The ICF is a useful tool to classify the health problems of people with non-neuropathic MPS. The planning of rehabilitation programs needs to covers all components of functioning to provide a biopsychosocial model of care. The ICF categories may direct health professionals to more effective targets.