Predictors of respiratory failure in Guillain-Barré syndrome: a 22 year cohort study from a single Italian centre.

BACKGROUND AND PURPOSE: The study aimed to identify predictors of respiratory failure leading to mechanical ventilation (MV) and tracheostomy in Guillain-Barré syndrome (GBS). METHODS: Two hundred and thirty adult cases admitted to the Neurology Unit of Modena, Italy, between January 2000 and December 2021 were studied. A cut-off of MV starting within 8 weeks from onset of weakness was used. Univariable, multivariable logistic and Cox regression analyses were used to determine which pre-specified clinical and diagnostic characteristics were capable of predicting MV and tracheostomy, due to weaning failure. The model was internally validated within the full cohort. The Erasmus GBS Respiratory Insufficiency Score was retrospectively applied. RESULTS: One hundred and seventy-six cases (76.5%) were classified as classical sensorimotor GBS and 54 (23.4%) as variants. Thirty-two patients (13.9%) needed MV: 84.3% required respiratory support within 7 days. Independent predictors of respiratory failure and MV were older age, facial, bulbar, neck flexor weakness, dysautonomia, axonal electrophysiological subtype, cardiovascular comorbidities and higher disability score at entry. There was no association with abnormal spinal fluid parameters nor with positive serology for recent infections. Twenty-two patients (68.7%) were ventilated for more than 7 days; 4.7% died within 8 weeks. The patients who required MV were treated more often with plasma exchange. Independent predictors of tracheostomy due to weaning trial failure were facial, bulbar, neck flexor weakness, autonomic dysfunction, associated cardiovascular morbidities and axonal electrophysiological subtype on nerve conduction study. CONCLUSIONS: Our study indicates distinct predictors of MV and tracheostomy in GBS patients.

Cardiac disorders worsen the final outcome in myasthenic crisis undergoing non-invasive mechanical ventilation: a retrospective 20-year study from a single center.

The study was performed to evaluate the impact of cardiological disorders on the outcome of myasthenic crisis (MC) requiring ventilation. The study includes 90 cases admitted to the Neurology Unit of Modena, Italy (January 2000 - September 2020). All patients were eligible for a non-invasive ventilation (NIV) trial. We analyzed the effect of cardiac comorbidities on the outcomes, which were the need of invasive ventilation, the risk tracheostomy for weaning failure and the duration of intensive care unit (ICU) stay Females were 58.9% and males 41.1%. Median age at diagnosis was 59 and at MC was 65. Patients were classified as early (EOMG) or late (LOMG), 34.4 and 65.6% respectively, according to age above or below 50; 85% of patients were anti- AChR antibody positive. Hypertension and cardiac diseases occurred at the diagnosis in 61 and 44.4%, respectively. Invasive mechanical ventilation (MV) was needed in 34% of cases. Nine subjects (10%) underwent tracheostomy because of weaning failure. Independent predictors of NIV failure were atrial fibrillation (AF), either parossistic or persistent (OR 3.05, p < 0.01), hypertensive cardiopathy (HHD) (OR 2.52, p < 0.01) and ischaemic heart disease (IHD) (OR 3.08, p < 0.01). Hypertension (HT) had no statistical effect on the outcomes. HHD was a predictor of weaning failure (OR 4.01, p = 0.017). Our study shows that HHD, AF and IHD increase the risk of NIV failure in MC receiving ventilation.

Predictors of outcome in patients with myasthenic crisis undergoing non-invasive mechanical ventilation: A retrospective 20 year longitudinal cohort study from a single Italian center.

About 20% of patients with myasthenia gravis (MG) may develop myasthenic crisis (MC) requiring ventilation, either invasive (MV) or non-invasive (NIV) and intensive unit care (ICU). NIV failure in patients with MC can occur up to 60% of cases admitted to ICU. Moreover it is not known the outcome of MC receiving NIV. Purpose of this study was to identify predictors of outcome in MC who underwent non-invasive ventilator support outside ICU setting. We enrolled 90 patients, 53 females and 37 males admitted to University Hospital of Modena (Italy) between January 2000 and September 2020. Median age at MC was 65 years. Thirty-four patients (37.8%) required MV. Thymectomy was performed in 45 cases, associated with thymoma in 55%, with hyperplastic thymus in 33%. First-line treatment was plasmaexchange (38.8%) or intravenous immunoglobulins (45.6%). Males exhibited higher risk of MV than females .Patients in MV were treated with plasmaexchange as first-line therapy . Our in-hospital mortality rate was low. Nine patients underwent tracheostomy which was significantly related to male gender. Comorbidities had significant effect on length of ICU .Our study confirms as predictors of prognosis in our patients male gender, older age at onset, infections as trigger, pneumonia.

Predictors of prognosis in type 1 myotonic dystrophy (DM1): longitudinal 18-years experience from a single center.

The aim of the study was to identify possible predictors of neurological worsening and need of non-invasive ventilation (NIV) in individuals affected by myotonic dystrophy type 1 (DM1), the most common form of adult-onset muscular dystrophy. METHODS: A retrospective observational cohort study was undertaken. Thirty-three patients with genetic diagnosis of DM1 were followed at our Neuromuscular unit in Modena. Abnormal trinucleotide repeat (CTG) expansion of dystrophy protein kinase gene (MDPK) on chromosome 19q 13.3 was the prerequisite for inclusion. The number of CTG repeats was determined. All the participants were older than 14 at the time of enrolment, therefore they could be included into the juvenile or adult form of the disease. Participants were neurologically evaluated every 6-8 months up to 18 years. Neurological impairment was assessed by Muscular Impairment Rating (MIRS), Medical Research Council (MRC), and modified Rankin (mRS) scales. The independent variables considered for prognosis were age at first evaluation, duration of the disease, CTG repeat number, gender, and presence of cardiac and vascular morbidities.Male patients were 51.5% and female patients 48.5%. Sixteen patients were younger than the mean age of 30.1 years, while the remaining 17 were up to 65. Twelve subjects (36.4%) underwent NIV before the end of follow-up. Muscle force and disability scores showed statistically significant deterioration (p < 0.001) during follow-up. The worsening was significantly higher among patients carrying higher number of CTG repeats and of younger age. The presence of cardio-vascular involvement has significant impact on neurological and respiratory progression.Neurological worsening is predicted by CTG expansion size, young age and presence of cardio-vascular morbidities.

A heroin addict with focal weakness.

A 24-year-old female with 5 year history of heroin abuse experienced painless stiffness of elbow joints and weakness of shoulder and upper limb muscles. She was injecting herself 4-6 times daily alternatively in the upper extremities, sparing the lower limbs. Electromyography (EMG) showed myopathic changes in clinically affected and unaffected muscles. Magnetic resonance imaging (MRI) revealed muscle fibrosis in directly injected muscles, whereas in subcutaneous fat and within muscles of anterior and posterior compartments of both thighs, not directly injected, there were signal changes supportive of oedema and inflammation. EMG and MRI were congruent in showing abnormalities in muscles not directly injected, suggesting long distant effects of heroin or adulterants with a mechanism either toxic or immunologically mediated.

Microwave-treated gelatin microspheres as drug delivery system.

The crosslinking process of natural macromolecules with microwave energy should have the potentiality to overcome the problems due to the toxicity of the residuals of chemical crosslinking agents and moreover of the "in vivo" biodegradation products of the chemical crosslinked macromolecule. To evaluate the effective crosslinking of the gelatin forming the microspheres, the water-soluble fraction at 37 degrees C, the water absorption capability, the free amino and free carboxylic acid groups of the gelatin were determined. The structural change in the gelatin microspheres has been detected by the porosity studies. Moreover, both the "in vitro" biodegradability and the biocompatibility of the gelatin microspheres microwave-treated after a subcutaneous injection into female albino guinea pigs were tested. As the results suggest only the gelatin microspheres microwave-treated for 10 min at an inlet temperature of 250 degrees C could have been modified by the crosslink formation among the macromolecular chains. The gelatin microspheres treated with the microwave energy were very well biodegraded as indicated both by the "in vitro" enzymatic degradation studies and mainly by the histopathological examination. This latter study has also demonstrated the biocompatibility of the gelatin microspheres crosslinked with the microwave energy. In order to evaluate the feasibility of the microwave crosslinking process for pharmaceutical applications, both the drug loading and the drug release processes were evaluated using diclofenac as drug model, either as acidic form or as sodium salt. The microspheres were swollen in aqueous solution of diclofenac sodium salt, followed by a washing procedure with cool water to maintain the sodium salt into the microspheres or with pH 1.5 HCl to induce the diclofenac precipitation. To increase the amount of diclofenac acid form in the microspheres, the procedure was repeated three times washing with pH 1.5 HCl after each swelling process. Both the X-ray diffractometry and thermal analysis investigations showed a different physical state of the two drug forms in the microspheres, i.e. the amorphous state of the sodium salt and the crystalline state of the acidic form. According to the experimental results, the drug is released from gelatin microspheres according to the drug loading and the drug solubility.