Clinical spectrum and diagnostic difficulties of infantile ponto-cerebellar hypoplasia type 1

We present the clinical and histopathological features and the diagnostic difficulties encountered in five children affected by a motor neuron disorder other than spinal muscular atrophy. Investigations performed suggested the diagnosis of ponto-cerebellar hypoplasia type 1 (PCH-1). Severe respiratory difficulty was present at birth in two of these children; hypotonia, arthrogryposis, microcephaly and nystagmus were present in all. Early and progressive bulbar involvement with swallowing difficulties and stridor was also a common feature in these infants. Severe cognitive delay was invariably present. Brain magnetic resonance imaging showed ponto-cerebellar hypoplasia in four children while striking atrophy of the cerebellar vermis and cerebellar hemispheres were present in the fifth child. Electrophysiological and pathological investigations of proximal muscles performed at presentation in all these children were not conclusive, while the post-mortem studies, or the study of distal muscles during life, showed a clear neurogenic picture. Genetic studies excluded involvement of the SMN gene, or of other genes located on chromosome 5q, confirming that ponto-cerebellar hypoplasia type 1 is a different entity from typical proximal spinal muscular atrophy.     

The "plastic bag syndrome". Compression of the digital neurovascular bundles by commercial plastic bags

We report a condition we call the "plastic bag syndrome" in which pressure on the neurovascular bundles causes temporary ischaemia in the distal part of the finger together with a neuropraxia of the digital nerves. Although in most cases the discomfort or numbness is fleeting, requires no medical assistance and is readily forgotten, in some instances the symptoms are such that medical advice is sought. Since the injury can lead to permanent damage and subsequent limitation in the use of the finger, we believe that the public should be advised to take simple precautions to prevent it from happening.     

Factor analysis of the psychosocial items of the EORTC QLQ-C30 in metastatic breast cancer patients participating in a psychosocial intervention study

The underlying factor structure of a subset of 12 items, which comprise the psychosocial subscales of the EORTC QLQ-C30 was explored in a group of women, all with metastatic breast cancer who were participating in a psychosocial intervention study. Two main factors were identified in this exploratory factor analysis, representing emotional distress and functional ability dimensions. A preliminary assessment of the external validity of the two factor structure was undertaken. The results support the validity of a summative emotional distress and functional ability score in this sample of patients. The functional ability score discriminated well for subgroups defined by clinical status indicators (e.g., performance status, pain, chemotherapy treatment, fatigue). The emotional distress subscale discriminated with respect to suffering, fatigue and sleep disturbance. Both subscales converged with related concepts measured by independent instruments, providing support for convergent validity. Summative index scores may be advantageous for application in particular research situations; applying quality adjustments in health policy analyses; for screening purposes; to monitor populations and make comparisons across broad groups and as stratification variables in clinical trials. Further research to confirm the 2 factor structure is required in other samples before the interpretation can be accepted with confidence.     

Cerebrospinal fluid probenecid studies: a reinterpretation

Probenecid is used to block the transport of acid monoamine metabolites from cerebrospinal fluid (CSF), on the assumption that the resultant rise in CSF concentrations of the metabolites will reflect presynaptic "turnover" of the parent monoamine. However, CSF levels of probenecid correlate with CSF levels of the metabolite, suggesting that the blockade is incomplete at the probenecid levels obtained in human studies. This article reviews the literature on CSF probenecid-metabolite correlations and presents data demonstrating variations in the correlations across diagnostic groups. These cross-diagnostic variations may be due to group differences in membrane transport characteristics and and confound attempts to "correct for" CSF probenecid concentrations in studies of monoamine turnover.