Idiopathic chronic inflammatory demyelinating polyneuropathy: an epidemiological study in Italy

AIM

The clinical and epidemiological characteristics of chronic inflammatory demyelinating polyneuropathy (CIDP) in an Italian population were assessed.

SUBJECTS AND METHODS

All subjects with a diagnosis of demyelinating neuropathy after 1990 in Piemonte and Valle d'Aosta (4,334,225 inhabitants) were considered. The diagnosis of CIDP was based on the research criteria of the American Academy of Neurology. 165 of 294 patients met the diagnostic criteria.

RESULTS

The crude prevalence rate was 3.58/100,000 population (95% CI 3.02 to 4.20). At the prevalence day, 76 (49.0%) cases had definite, 67 (43.2%) probable and 12 (7.7%) possible CIDP; disability was mild in 105 (67.7%) cases, moderate in 32 (20.6%) and severe in 18 (11.6%). The course was remitting-relapsing in 40 cases (25.8%), chronic progressive in 96 (61.9%) and monophasic in 19 (12.3%). Considering the 95 patients whose disorder presented in the period 1995-2001, the mean annual crude incidence rate was 0.36/100,000 population (95% CI 0.29 to 0.44), with a male to female ratio of 2.3:1. 14 cases were affected by diabetes mellitus. In multivariate analysis, factors related to severe disability at the prevalence day were: age >60 years; failure of immunomodulating therapies at the time of diagnosis; worse disability at nadir; and chronic course.

CONCLUSION

Incidence and prevalence rates of CIDP in Italy were higher than those observed in most previous studies. At the prevalence day, more than 80% of cases had a mild or moderate disability, indicating either a good response to immunomodulating therapy or a tendency of CIDP to have a mild course in most cases.

Ischaemic stroke, factor V Leiden heterozygosity and left atrial thrombosis in sinus rhythm: a case report

We describe a 63-year-old man in sinus rhythm (SR) with an ischaemic stroke involving basal ganglia region on the right side. The patient was known to be heterozygous for factor V Leiden (FVL) mutation. On diagnostic work-up, no arterial sources of embolism were found. Transoesophageal echocardiography evidenced a left atrial (LA) thrombosis without relevant cardiopathies. LA thrombosis is generally associated to atrial fibrillation, atrial enlargement, mitral valve stenosis and left ventricular dysfunction, whereas mitral regurgitation is considered protective. To our knowledge, this is the first report of cardioembolic stroke related to a LA thrombosis in a patient in SR without risk factors for thrombus formation except for FVL heterozygosity.

Positive effects of tertiary centres for amyotrophic lateral sclerosis on outcome and use of hospital facilities

OBJECTIVE

To evaluate the effects of tertiary centres for amyotrophic lateral sclerosis (ALS) on ALS outcome and the use of hospital facilities.

METHODS

The study was based on the data of an epidemiological, prospective, population-based register on ALS (Piemonte and Valle d'Aosta Register for amyotrophic lateral sclerosis, PARALS). The 221 patients recruited between 1995 and 1996 were prospectively followed up for outcome and use of hospital-based services.

RESULTS

In all, 97 patients were followed up by tertiary ALS centres and 124 by general neurological clinics. Patients followed up by tertiary ALS centres were found to be 4 years younger and underwent percutaneous endoscopic gastronomy and non-invasive positive-pressure ventilation more often. Patients followed up by tertiary ALS centres were found to have a considerably longer median survival time (1080 v 775 days), even when stratifying by age, site of onset and respiratory function at diagnosis. In Cox multivariate analysis, attending a tertiary ALS centre was observed to be an independent positive prognostic factor. Moreover, patients attending a tertiary ALS centre were admitted to hospital less often (1.2 v 3.3) and were more frequently admitted for planned interventions. Conversely, patients followed up by general neurological clinics were more frequently admitted for acute events. Also, the hospital stay was considerably shorter for patients attending tertiary ALS centres (5.8 v 12.4 days).

CONCLUSIONS

Improved survival was seen in patients with ALS attending tertiary ALS centres, independently from all other known prognostic factors, possibly through a better implementation of supportive treatments. Moreover, because of these centres, the hospitalisation rate was markedly reduced, thus offering a cost-effective service to patients with ALS and to the community as a whole.

Paclitaxel and pegylated liposomal doxorubicin in recurrent head/neck cancer: An unexpected administration interval-dependent pharmacokinetic interaction

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Background: Combination of paclitaxel (PTX) with pegylated liposomal doxorubicin (PLD) is an interesting opportunity for recurrent head/neck cancer treatment. Their pharmacokinetic (PK) behavior could be dependent not only on PTX excipient (polyethoxylated castor oil) interference, but also on different iv administration interval between the two drugs. The study endpoint was to evaluate any possible administration interval-dependent PK interaction, when PLD infusion start is delayed from 0 to 24 h after PTX infusion end. Methods: 24 patients affected by recurrent cisplatin pre-treated squamous cellhead/neck cancer were enrolled, receiving PTX 80 mg/m2 q 1w and PLD 12.5 mg/m2 q 2w for 6w/2w rest. Administration interval was 0 h at d1 (PTX-PLD 0) and 24 h at d15 (PTX-PLD 24). Blood sampling was performed at d1–15, PTX and PLD blood levels were analyzed by high performance liquid chromatography techniques, while PK parameters by non-compartmental analysis. Results: PTX PK parameters had large statistically significant differences (median/IQR, PTX-PLD 0 vs. PTX-PLD 24, Mann-Whitney test): Cmax 261/219–531 vs. 407/250–1473 ng/ml p=0.142, AUC 869/688–1331 vs. 3361/969–7853 ng*h/ml p=0.013, Kel 0.39/0.26–0.57 vs. 0.11/0.02–0.26 h⁁−1 p=0.001, Cl 153/89–198 vs. 41/17–138 l/h p=0.013. Similarly, PLD Cmax and AUC were higher in PTX-PLD 24 (Cmax 5.1/3.3–8.1 vs. 6.8/5.3–7.8 mg/l p=0.043, AUC 341/104–1472 vs. 603/106–1006 mg*h/l p=1.000). The overall response rate was 37.5%, including 1 CR (4%); median response duration was 5.5 months (range, 2–16), median overall survival 10 months (range, 2–25+). Conclusions: This exploratory study, having a favourable palliative role in heavily pre-treated patients, showed that PTX PK profile is unexpectedly affected by a different administration interval. In PTX-PLD 0, PTX AUC is fourfold reduced, with a similar increase in Cl, totally due to Kel alteration: therefore, patients could be underexposed to PTX. PLD PK behavior confirmed previous studies results, in which PTX modified PLD disposition, prolonging the duration of its elimination phase and increasing total body exposure to PLD.

No significant financial relationships to disclose.

Gabapentin vs. amitriptyline in painful diabetic neuropathy: an open-label pilot study

The objective of this study was to compare the efficacy and tolerability of gabapentin and amitriptyline monotherapy in painful diabetic neuropathy. This was a 12-week, open-label, prospective, randomized trial. Twenty-five type-II diabetic patients with pain attributed to diabetic neuropathy and a minimum score of 2 on a pain intensity scale ranging from 0 (no pain) to 4 (excruciating pain) were randomized to receive either gabapentin, titrated from 1,200 mg/day to a maximum of 2,400 mg/day, or amitriptyline, titrated from 30 mg/day to a maximum of 90 mg/day. Both drugs were titrated over a 4-week period and maintained at the maximum tolerated dose for 8 weeks. The main outcome measures were weekly pain intensity and paresthesia intensity, measured on two categorical scales. Thirteen patients received gabapentin and 12 received amitriptyline. All 25 patients completed the trial. Gabapentin produced greater pain reductions than amitriptyline (mean final scores were 1.9 vs. 1.3 points below baseline scores; P = 0.026). Decreases in paresthesia scores also were in favor of gabapentin (1.8 vs. 0.9 points; P = 0. 004). Adverse events were more frequent in the amitriptyline group than in the gabapentin group: they were reported by 11/12 (92%) and 4/13 (31%) of patients, respectively (P = 0.003). Side effects were the main limiting factor preventing dose escalation. Gabapentin produced greater improvements than amitriptyline in pain and paresthesia associated with diabetic neuropathy. Additionally, gabapentin was better tolerated than amitriptyline. Further controlled trials are needed to confirm these preliminary results.

State of stupor from valproic acid during chronic treatment: case report

We describe the case of a 26 years old woman in chronic therapy with phenobarbital, carbamazepine, valproic acid (VPA) and clonazepam who showed a hyperammonemic encephalopathy after an increase in dosage of VPA. Similar cases have been reported, but with acute-subacute onset and no correlation with the plasma levels of VPA. Our case suggests the possibility that this toxic effect occurs during chronic treatment too, when the dosage of VPA is increased.

In vivo and in vitro effect of liver on somatomedin generation

The serum concentration of circulating somatomedins was measured in the blood of healthy donors and subjects with hepatic cirrhosis, and in culture media from in vitro explants of healthy and cirrhotic human liver. Serum levels of somatomedin bioactivity were significantly lower in cirrhotic subjects (0.42 +/- 0.03 U/ml; M +/- SEM) compared with age matched controls (0.99 +/- 0.03 U/ml). Radioreceptor assay of somatomedin concentrations confirmed this reduction in cirrhotic patients (0.89 +/- 0.06 U/ml) compared with controls (1.32 +/- 0.05 U/ml). A parallel reduction in somatomedin circulating binding ability was also observed (99.43 +/- 7.28% in cirrhotic and 123.5% +/- 10.8% in normal subjects). In vitro explants from normal human liver tissue produced a significant increase (0.57 +/- 0.09 U/ml) in somatomedin bioactivity contained in the medium (0.29 +/- 0.06 U/ml), while a decreased bioactivity (0.12 +/- 0.06 U/ml) was observed with explants of cirrhotic livers. These results support a role of liver in the biosynthesis of both somatomedin and somatomedin binding protein.