Acid maltase deficiency: treatment of respiratory insufficiency with cuirass respirator

Fluorescent Sensor Array for Quantitative Determination of Saccharides

Accurate monitoring of sugar levels is essential for many fields from food industry to human health. Here, we developed FRET-based dual chromophore sensors for saccharides that form oxazolidine boronate and may be employed as a noninvasive method for monitoring of sugar levels in biological fluids, namely, urine. The saccharide-binding properties of the sensors were studied using fluorescence spectroscopy and utilized in the determination of saccharides in a high-throughput manner. Here, two fluorescent sensors were successful in the classification of nine different monosaccharides and disaccharides with 100% correct classification. Furthermore, the dual chromophore self-assembled sensors were successfully utilized for the quantitative determination of important carbohydrates such as glucose in the presence of competitive saccharides (fructose) and in complex media (urine) without sample pretreatment. The present fluorescent sensors allow for quantification of glucose in a concentration range of 0-60 mM, which matches the concentration range of frequently used urinalysis test strips.

[Treatment of subcutaneous and mediastinal emphysema with cuirass ventilation in a patient with Pompe disease undergoing non-invasive positive pressure ventilation]

We report a case of subcutaneous and mediastinal emphysema in a 39-year-old woman with late-onset Pompe disease who was undergoing non-invasive positive pressure ventilation (NPPV). Although the patient had a history of pneumothorax, she did not present with pneumothorax at the time of admission. She had not undergone adequate respiratory rehabilitation, which resulted in decreased respiratory compliance. We speculated that the emphysema had been caused by an increase in the airway pressure due to NPPV. Decrease in inspiratory pressure of NPPV from 14 cm H2O to 9 cm H2O made the patient dyspneic and hypoxic. Cuirass ventilation by itself resulted in dyspnea and hypoxia. By using a combination of cuirass ventilation (control mode) and NPPV (assist/control mode), we were able to decrease the inspiratory pressure to 7 cm H2O. After 26 days of treatment, the patient recovered from subcutaneous and mediastinal emphysema. After the treatment, her maximum inspiratory capacity was increased from 400 ml to 600 ml, which indicates increased thoracic compliance. Thus, a combination of cuirass ventilation and NPPV is beneficial in managing barotrauma that may occur during NPPV in a respirator-dependent patient.

The natural course of non–classic Pompe’s disease; a review of 225 published cases

Pompe's disease is a neuromuscular disorder caused by deficiency of lysosomal acid alpha-glucosidase. Recombinant human alpha- glucosidase is under evaluation as therapeutic drug. In light of this development we studied the natural course of cases not fitting the definition of classic infantile Pompe's disease. Our review of 109 reports including 225 cases shows a continuous spectrum of phenotypes. The onset of symptoms ranged from 0 to 71 years. Based on the available literature, no criteria to delineate clinical sub-types could be established.A common denominator of these cases is that first symptoms were related to or caused by muscle weakness. In general, patients with a later onset of symptoms seemed to have a better prognosis. Respiratory failure was the most frequent cause of death. CK, LDH, ASAT, ALAT and muscle glycogen levels were frequently but not always elevated. In most cases a muscle biopsy revealed lysosomal pathology, but normal muscle morphology does not exclude Pompe's disease. In 10% of the cases in which the enzyme assay on leukocytes was used, a normal alpha-glucosidase activity was reported. Data on skeletal muscle strength and function, pulmonary function, disability, handicap and quality of life were insufficiently reported in the literature. Studies of non-classic Pompe's disease should focus on these aspects, before enzyme replacement therapy becomes generally available.

Muscle MRI in adult-onset acid maltase deficiency

We report the spectrum of muscle involvement on magnetic resonance imaging in 11 patients with a molecularly confirmed diagnosis of adult-onset acid maltase deficiency at different clinical stages. Muscle magnetic resonance imaging showed a selective progressive pattern of muscle involvement with a constant involvement of the adductor magnus and semimembranosus at the early stage of the disease and a later fatty infiltration of the long head of the biceps femoris, semitendinosus and of the anterior thigh muscles. In the advanced phases a selective sparing of sartorius, rectus, and gracilis muscles and peripheral portions of the vastus lateralis was also evident. Muscle strength and magnetic resonance imaging findings were positively correlated. The results suggest that muscle magnetic resonance imaging may provide valuable diagnostic guidance for the assessment of accurate selective muscular involvement in acid maltase deficiency and may help monitor the progression of the disorder. Further control studies in a larger cohort are needed to evaluate the specificity of these findings.

Muscle computed tomography in adult-onset acid maltase deficiency

Nine patients with adult-onset acid maltase deficiency (Pompe's disease) were examined clinically and with computed tomography (CT). The CT scan showed early and severe involvement of the muscles of trunk and thighs, with selective sparing of the tensor fasciae latae, short head of biceps femoris, gracilis, and sartorius muscles. Shoulder and leg muscles were less affected. The disease spread over the years from trunk to extremities. Muscle strength and CT findings were positively correlated.

Clinical variability in adult-onset acid maltase deficiency: report of affected sibs and review of the literature

Acid maltase deficiency (AMD) is a rare cause of muscle disease in adult patients. The present report of 2 sibs and review of 36 previously reported cases illustrates the vast clinical variability in adult-onset AMD. This is 1 of only 3 reports to document tongue weakness and enlargement in an adult with AMD. The presenting signs and symptoms usually include progressive limb weakness, restrictive lung disease, or both. Consistent supportive abnormalities include a modest elevation in serum CK, a reduction in the forced vital capacity, and abnormal spontaneous activity (that is, myotonic discharges or fibrillations) in resting muscles during needle electromyography. The clinical spectrum is also extended to include distal limb weakness, scapular winging, asymmetric muscle weakness, and tongue involvement.

Clinical applications of body ventilators

Interest has been increasing in providing ventilatory support in the home for patients with chronic respiratory failure, mainly with the use of positive pressure ventilation via a chronic tracheostomy. However, body ventilators that assist ventilation by applying intermittent negative or positive pressure to the thorax, abdomen, or airway without requiring an artificial airway, can offer distinct advantages for selected patients over systems requiring a permanent airway. These ventilators include the iron lung, portable lung (Portalung), pneumowrap, chest cuirass, pneumobelt, rocking bed, and positive pressure provided via a face or nose mask. They have successfully stabilized or reversed chronic hypercarbia when used intermittently in patients with slowly progressive chronic respiratory failure due to certain neuromuscular diseases and kyphoscoliosis. How they achieve this stabilization has not been clarified, but reversal of chronic respiratory muscle fatigue following periodic rest probably contributes. These ventilators are generally less effective than positive pressure ventilation through a tracheostomy and should be reserved for patients with relatively stable chronic respiratory failure and intact upper airways. However, they have the advantages of simpler operation and less expense, and they allow maintenance of a normal airway.

Adult onset acid maltase deficiency. Distribution and progression of clinical and pathological abnormality in a family

The adult onset form of acid maltase deficiency (Type IIb) clinically affects only skeletal muscle. Proximal weakness is more severe in legs than arms and involvement of respiratory muscles is prominent in about a third of the cases. In three siblings with the disease, the severity of limb weakness was related to age and duration of disease. Respiratory muscle involvement was a feature in two of the patients. The pathological abnormality was more marked in quadriceps than deltoid, and was strikingly patchy in distribution within these muscles. In one case, vacuolar change was not evident by light microscopy in two quadriceps biopsies taken 2 years apart. There is thus a spectrum of clinical and pathological expression of the disorder even in a single sibship.