Musculoskeletal manifestations of lysosomal storage disorders.

Lysosomal storage disorders (LSDs), a heterogeneous group of inborn metabolic disorders, are far more common than most doctors presume. Although patients with a severe LSD subtype are often readily diagnosed, the more attenuated subtypes are frequently missed or diagnosis is significantly delayed. The presenting manifestations often involve the bones and/or joints and therefore these patients are frequently under specialist care by (paediatric) rheumatologists, receiving inadequate treatment. Since effective disease-specific treatments, including enzyme replacement therapy and stem cell transplantation, have become available for certain LSDs and timely initiation of these treatments is necessary to prevent the development of severe, disabling and irreversible manifestations, early diagnosis has become essential. The challenge is to raise awareness for better recognition of the presenting signs and symptoms of LSDs by all doctors who may encounter these patients, including rheumatologists.

Accuracy and inter-observer variation in the classification of dysarthria from speech recordings.

BACKGROUND: Dysarthria may be classified as flaccid, spastic, ataxic, hypokinetic, choreatic, dystonic, or mixed. We hypothesized that in routine neurological practice the reliability and accuracy of perceptual analysis alone in the classification of dysarthria is low and that this classification is mainly based on the clinical context rather than on the perception of speech. We therefore studied the accuracy and the inter- observer agreement in the classification of dysarthrias on the basis of perceptual analysis alone. METHODS: Seventy two neurologists and neurological trainees classified recorded speech samples of 100 patients as flaccid, spastic, ataxic, extrapyramidal, or mixed dysarthria, or as not dysarthric. All observers were blinded to the patients' final diagnosis, which was based on all clinical features and investigations. In the analysis the observers were arranged in eight groups of nine observers, or four paired groups with similar levels of clinical experience. Together, the observers in a given group rated all 100 recordings. RESULTS: The accuracy of the classification was poor (35 % were classified correctly) and the inter-observer agreement between paired groups low (kappa 0.16 to 0.32). The level of experience in neurology did not have a significant influence. CONCLUSION: Neurological trainees as well as experienced neurologists have great difficulty in identifying specific types of dysarthria on the basis of perceptual analysis alone. In clinical practice this probably means that most neurologists will classify dysarthria in the context of other features from neurological examination or ancillary investigations.

[Umbilical cord blood from an unrelated donor as source for stem cell transplantations in inborn errors of metabolism]. / Navelstrengbloed van een onverwante donor als bron voor stamceltransplantaties bij aangeboren stofwisselingsziekten.

In certain inborn errors of metabolism, an allogeneic stem cell transplantation is able to prevent disease progression. This is only possible when the stem cell transplantation (SCT) is performed early in life, before cerebral involvement has occurred. In addition to bone marrow and peripheral blood, unrelated umbilical cord blood appears to be an effective stem cell source as well. Important advantages of umbilical blood as stem cell source are: the time between diagnosis and SCT can be considerably reduced; there is a greater chance of finding a suitable donor and the risk of graft-versus-host disease and viral transmission is decreased. By far the most common disease in the group of inborn metabolic errors for which SCTs are performed is Hurler's disease. In these patients, the percentage of successful transplantations is considerably higher after the use ofunrelated cord blood than when bone marrow or peripheral blood is used as a stem cell source. In addition, donor chimerism occurred significantly more often in those patients who had received unrelated umbilical cord blood. There are also potential disadvantages attached to the use of umbilical blood as stem cell source: the possibility of only one donation per donor and less adaptive immunity following umbilical blood SCT with an increased risk of reactivation of a previous viral infection. However, these disadvantages are less applicable to young children with inborn errors of metabolism. The improvement of transplantation techniques and the availability of this new stem cell source could improve the success rate of this procedure and consequently the prognosis of these severely affected patients.

[From gene to disease; Menkes disease: copper deficiency due to an ATP7A-gene defect]. / Van gen naar ziekte; de ziekte van menkes: koperdeficiëntie door een ATP7A-gendefect.

Menkes disease is an X-linked recessive disorder characterized by neurological deterioration, failure to thrive, peculiar hair and death in childhood, secondary to mutations in the ATP7A gene. The ATP7A gene encodes for a copper transporting P-type ATPase (ATP7A), which is ubiquitously expressed. A defect of the ATP7A protein leads to both a reduced transport of copper from the intestine into the circulation and into the central nervous system, as well as reduced transport of copper into the Golgi apparatus for incorporation into various copper-dependent enzymes. This results in a systemic copper deficiency as well as reduced activity of various copper-dependent enzymes. The reduced activity of these copper-dependent enzymes accounts for most of the characteristic features ofMenkes disease patients.

Therapeutic strategies for epidemic Kaposi's sarcoma.

Kaposi's sarcoma (KS) remains the most commonly diagnosed malignancy in HIV-infected patients, and is one of the AIDS-defining diagnoses. Several different therapeutic options are available, but the optimal therapy is still unclear. The incidence of KS has sharply declined since highly active antiretroviral therapy (HAART) became widely available, making HAART indispensable in the treatment of epidemic KS. HAART can be given alone or in combination with systemic and local therapy. Systemic therapy can be given in disseminated, progressive or symptomatic disease. Treatment options are interferon-alpha and chemotherapy including pegylated-liposomal anthracyclines and paclitaxel. For local disease, radiotherapy, intralesional chemotherapy or cryotherapy may be used. In resource-limited settings, intravenous vincristine, oral etoposide or intramuscular bleomycin may be feasible options. Other therapies, such as angiogenesis inhibitors, are under investigation in clinical trials.