Can we lower the platelet threshold of ≥ 50 × 109/L for performing a lumbar puncture safely in patients with hematological malignancies?

Lumbar punctures (LP) are routinely used to administer intrathecal chemotherapy for children and adults with hematologic malignancies. The current guidelines suggest a platelet threshold of ≥ 50 × 10⁹/L prior to LP for intrathecal chemotherapy (ITC). This can be challenging in patients with hematological malignancies who are thrombocytopenic. We conducted a retrospective chart review of 900 LPs for ITC and compared adverse events in patients with a platelet count of ≥ 50 × 10⁹/L and < 50 × 10⁹/L. Cohort 1 included 682 LPs (75.8%) with a pre-procedure platelet count ≥ 50 × 10⁹/L, and cohort 2 included 218 LPs (24.2%) with a pre-procedure platelet count < 50 × 10⁹/L. Cohort 2 was further subdivided into pre-procedure platelet counts of 41 × 10⁹/L-49 × 10⁹/L (n = 43), 31 × 10⁹/L-40 × 10⁹/L (n = 77), 21 × 10⁹/L-30 × 10⁹/L (n = 84), and 11 × 10⁹/L-20 × 10⁹/L (n = 14). Among 900 LP procedures, a pre-procedure platelet count < 50 × 10⁹/L did not demonstrate a higher rate of post-procedure adverse events (6.5% vs 6.8%, p = 0.8237). When cohort 2 was further stratified, the cohort with a pre-procedure platelet count of 21 × 10⁹/L-30 × 10⁹/L had the highest percentage of complications from LP (9.5%) and the highest rates of traumatic taps with observed LP RBC count > 200 (35.7%, p = 0.0015). The rate of red blood cells (RBC) in the CSF was significantly higher in the group with platelets < 50 × 10⁹/L with observed LP RBC count ≥ 200 (31.2% vs 20.5%, p = 0.0016), ≥ 500 (27.1% vs 14.6%, p < 0.0001), and ≥ 1000 (23% vs 11.6%, p < 0.0001). No instances of epidural hematomas were seen. We found no significant difference in bleeding complications between patients undergoing LPs for ITC with a platelet count above or below 50 × 10⁹/L.

Effect of continuous positive airway pressure treatment on the subsequent EEG spectral power and sleepiness over sustained wakefulness in patients with obstructive sleep apnea-hypopnea syndrome

OBJECTIVE

To determine whether sleepiness and its evolution over sustained wakefulness could be reversed by nasal continuous positive airway pressure (CPAP) therapy in patients with obstructive sleep apnea-hypopnea syndrome (OSAHS).

METHODS

Twelve OSAHS patients underwent three 32-h sessions of study: one before CPAP therapy (T0), the second (T3) and the third (T6), respectively, after 3 and 6 months of therapy. Each session included one night of sleep followed by 24 h of sustained wakefulness, during which EEG recordings and subjective ratings were performed every hour.

RESULTS

The waking EEG in treated OSAHS patients was partially improved after 3 months of CPAP and their subjective complaint of sleepiness was normalized after 6 months. Theta power (3.9-7.8 Hz) was decreased as well as its time course during the diurnal period but beta power (12.7-29.2 Hz) remained higher.

CONCLUSIONS

CPAP partially reverses waking EEG abnormalities in OSAHS patients with reduced theta activity after 3 months and removes the subjective complaint of sleepiness after 6 months. Nevertheless, the persistence of increased beta activity in treated patients suggests that efforts to stay awake remain strong after CPAP treatment.

SIGNIFICANCE

CPAP influences the EEG's time course over sustained wakefulness in a frequency-specific manner in OSAHS patients.

Severity of obstructive sleep apnoea/hypopnoea syndrome and subsequent waking EEG spectral power

It is well known that most patients with obstructive sleep apnoea/hypopnoea syndrome (OSAHS) suffer sleepiness, although the underlying mechanisms of this relationship remain unclear. The present study examined the relationship between nocturnal variables and the subsequent waking electroencephalogram (EEG), in order to determine if sleepiness was related to OSAHS severity and due to sleep fragmentation or to nocturnal hypoxaemia. In total, 12 moderate-to-severe OSAHS patients underwent a total sleep night followed by a 24-h period of sustained wakefulness where the waking EEG was measured every hour. The results showed that alpha (7.9-12.6 Hz) and beta (12.7-29.2 Hz) activities were strongly related to OSAHS severity, mainly reflected by the apnoea index. Moreover, spectral power in most of the waking EEG components was significantly correlated with nocturnal hypoxaemia indices, namely alpha and beta activity when hypoxaemia becomes severe. However, no correlation was found between the waking EEG and sleep fragmentation parameters. In conclusion, the present results suggest that the difficulty in maintaining an optimal level of alertness, reflected by a higher activity in awake alpha and beta bands (7.9-29.2 Hz) in obstructive sleep apnoea/hypopnoea syndrome, was better explained by: 1) the apnoea as opposed to the hypopnoea index; and 2) nocturnal hypoxaemia as opposed to sleep fragmentation.

Prostaglandin-mediated control of rat brain kynurenic acid synthesis--opposite actions by COX-1 and COX-2 isoforms

Kynurenic acid (KYNA), an endogenous glutamate-receptor antagonist preferentially blocking NMDA-receptors, has analgesic properties and has also been implicated in the pathophysiology of schizophrenia. Recently, the non-steroid anti-inflammatory drug (NSAID) diclofenac was found to increase rat brain KYNA. Here, we analyze whether cyclooxygenase (COX)-1 or COX-2 modulate the levels of rat brain KYNA. The non-selective COX-inhibitor diclofenac (50 mg/kg, i.p.) or indomethacin (50 mg/kg, i.p.), a non-selective inhibitor with a preferential selectivity for COX-1, produced an elevation in brain KYNA. In contrast, the COX-2 selective inhibitors parecoxib (25 mg/kg, i.p.) or meloxicam (5 mg/kg, i.p.) decreased brain KYNA. Both elevation and lowering of brain KYNA by indomethacin or parecoxib, respectively, were prevented by the prostaglandin E1/E2 agonist misoprostol (1 mg/kg, s.c.). It is proposed that increased brain KYNA formation induced by NSAIDs displaying an inhibitory action on COX-1 contribute to their analgesic efficacy as well as to their psychiatric side effects.

[Cortical arousal, autonomic arousal. Evaluation techniques and clinical importance]

The respiratory disorders expressed by obstructive hypopneas and apneas during sleep, as well as the sequences of crescendo in respiratory effort without hypopneas or apneas which define the upper airway resistance syndrome, terminate with (thanks to) an arousal, defined by EEG changes. In some cases, the activation of the central nervous system is restricted to a sympathetic activation, which has been mainly studied in the cardiovascular area, and is not always accompanied by a cortical arousal. Various approaches (heart rate, blood pressure, pulse transit time, peripheral arterial tonometry) make the identification of sympathetic activation possible. Sympathetic activation seems to be more sensitive than cortical arousal to the stimulations generated by the respiratory system via an activation of mechanoreceptors stimulated by the increased respiratory effort in response to total or partial occlusion of the upper airway. The mechanisms of the cortical or autonomic arousal are not fully understood, but their detection could be a diagnostic tool for the identification of such disorders. Such tools are currently under validation.

Treating rheumatoid arthritis early with disease modifying drugs reduces joint damage: a randomised double blind trial of sulphasalazine vs diclofenac sodium

BACKGROUND

Current disease management in rheumatoid arthritis (RA) has moved towards "inverting the therapeutic pyramid" by introducing disease-modifying anti-rheumatic drugs (DMARDs) early. Despite the logic of early DMARD therapy, there is a dearth of supportive evidence for this approach. We report a randomised controlled trial comparing sulphasalazine monotherapy with diclofenac monotherapy in early RA. The primary aim was to provide unequivocal evidence that early DMARDs prevent erosive damage. The secondary aim was to evaluate if sulphasalazine used alone has comparable symptomatic benefits to NSAIDs.

METHODS

117 patients with RA for under 12 months of diagnosis (mean 2 months) were randomised (62 sulphasalazine; 55 diclofenac). Sulphasalazine patients comprised 76% women, and 58% were rheumatoidfactor positive. Diclofenac patients comprised 74% women, and 54% were seropositive. 36% completed 12 months of therapy (16 sulphasalazine; 26 diclofenac); sulphasalazine was given for a mean period of 21 weeks and diclofenac for a mean period of 33 weeks. Results were analysed on an intention to treat basis.

RESULTS

After 12 months the mean number of new erosions in patients randomised to receive sulphasalazine was 2.0 (95%CI 0.9, 3.1) and in patients randomised to receive diclofenac was 7.5 (95%CI 4.1, 10.9; p = 0.002 by Student's unpaired t-test). An analysis of valid compliant completers showed the mean number of new erosions in patients who received 12 months therapy with sulphasalazine was 2.3 (95%CI 0.6, 4.0) and in patients who received 12 months diclofenac was 10.5 (95%CI 5.0, 15.9; p = 0.018 by Student's unpaired t-test). The Ritchie articular index, swollen joint counts and pain scores decreased with both sulphasalazine and diclofenac, with mean falls in both groups of 15-20% at 2 weeks and 30-40% at 4 and 8 weeks. There were no differences between treatments. Disease activity scores showed similar highly significant mean decreases within both treatment groups (P < 0.001 in all cases) of 0.5 at 2 weeks and 1.0 at 4 weeks; at 12 and 26 weeks they were significantly lower with sulphasalazine (p = 0.036 and 0.045). 75% of the patients given sulphasalazine and 65% of those given diclofenac had one or more adverse events with no major differences between treatments.

CONCLUSIONS

These results show that an accelerated dosing schedule of sulphasalazine has identical effects to diclofenac in reducing symptoms, indicating it is a rapidly effective DMARD. They also provide unequivocal evidence, analysed on an intention to treat basis, that early treatment with sulphasalazine significantly reduces the extent of radiological progression in active RA.

Alterations in T gamma cells in patients with chronic idiopathic thrombocytopenic purpura

The number and percentage of T cells bearing Fc gamma receptors (T gamma) was quantitated in peripheral blood of patients with the autoimmune disease chronic ITP. In over half the patients, low initial percentages were obtained, the great majority of which returned to within the normal range after incubation under capping conditions. The phenomenon could be reproduced by pretreating normal T cells with immune complex containing sera or aggregated HGG. Furthermore, a reversible reduction in T gamma cells was observed in control patients with nonimmune thrombocytopenia and in pregnancy. In each case an association was observed between the reduced T gamma cell levels and the presence of circulating immune complexes, which suggested that the results could be explained by masking of Fc gamma receptors with preformed IgG-containing complexes. By contrast, patients with other autoimmune diseases such as scleroderma and rheumatoid arthritis had high or normal numbers of T gamma cells, respectively. Taken together, the findings do not support the existence of a gross deficiency of suppressor cells in patients with autoimmune disease and emphasize the need for caution in selection of markers for identification of T cell subsets.

Alterations in T gamma cells in patients with chronic idiopathic thrombocytopenic purpura

The number and percentage of T cells bearing Fc gamma receptors (T gamma) was quantitated in peripheral blood of patients with the autoimmune disease chronic ITP. In over half the patients, low initial percentages were obtained, the great majority of which returned to within the normal range after incubation under capping conditions. The phenomenon could be reproduced by pretreating normal T cells with immune complex containing sera or aggregated HGG. Furthermore, a reversible reduction in T gamma cells was observed in control patients with nonimmune thrombocytopenia and in pregnancy. In each case an association was observed between the reduced T gamma cell levels and the presence of circulating immune complexes, which suggested that the results could be explained by masking of Fc gamma receptors with preformed IgG-containing complexes. By contrast, patients with other autoimmune diseases such as scleroderma and rheumatoid arthritis had high or normal numbers of T gamma cells, respectively. Taken together, the findings do not support the existence of a gross deficiency of suppressor cells in patients with autoimmune disease and emphasize the need for caution in selection of markers for identification of T cell subsets.