Antonella Romaniello

Laser evoked potentials for assessing sensory neuropathy in human patients

Sensory neuropathy usually impairs tactile sensations related to large myelinated afferents (Abeta) as well as thermal-pain sense related to small myelinated (Adelta) and unmyelinated (C) afferents. By selectively affecting large or small fibres, some sensory neuropathies may also provoke a dissociated sensory loss. Standard nerve conduction studies and somatosensory evoked potentials assess Abeta-fibre function only. Laser pulses selectively excite free nerve endings in the superficial skin layers and evoke Adelta-related brain potentials (LEPs). From earlier studies and new cases we collected data on 270 patients with sensory neuropathy. LEPs often disclosed subclinical dysfunction of Adelta fibres and proved a sensitive and reliable diagnostic tool for assessing small-fibre function in sensory neuropathy.

Trigeminal responses to laser stimuli

The majority of the studies on laser evoked potentials (LEPs) have been focused on hand and foot stimulations and only lately on the trigeminal system. Because of a high receptor density in the facial skin and the very short conduction distance, LEP recordings after trigeminal stimulation are easier and quicker than those after stimulation of the limb extremities. Laser pulses with a stimulus intensity close to perception threshold can evoke well-defined LEPs. Few trials are sufficient to yield stable and reproducible averages. Even ultralate LEPs related to the C-fibre input are comparatively easily obtained from the trigeminal territory. The brain generators of the main LEP waves are probably very close for the trigeminal and limb stimulations. Trigeminal LEPs have been found absent or delayed in patients with trigeminal neuralgia, trigeminal neuropathies, posterior fossa tumors, and brainstem infarctions or demyelinating plaques. Conversely, trigeminal LEPs appear to be enhanced in patients with migraine. High-intensity pulses directed to any trigeminal division also elicit reflex responses: a blink-like reflex in the orbicularis oculi and a single silent period in the contracting masseter muscle. The availability of a neurophysiological method of assessing function of the trigeminal nociceptive pathways reaching both the cerebral cortex and the brainstem reflex circuits, has provided new opportunities for investigating the pathophysiology of orofacial pain syndromes.

Prepulse inhibition of the blink reflex by laser stimuli in normal humans.

The subcortical integrative effects of laser-induced activation of pain ascending tracts were examined in 11 healthy volunteers, aged 22-52 years. Subjects underwent either CO2 laser stimulation at the dorsum of the hand, electrical stimulation of digital nerves at the 3rd finger, or mechanical taps to the first dorsal interosseous space, preceding a blink reflex elicited by a supraorbital nerve electrical stimulus. The percentage inhibition induced in the R2 response of the blink reflex was similar for the three different stimulus modalities, but occurred at a different time interval. Compared to control trials, the R2 response of the test trials was a mean of 23.1% at the interval of 250 ms with laser stimuli, 17.4% at the interval of 100 ms with electrical stimuli to the 3rd finger, and 20.6% at the interval of 90 ms with a mechanical tap to the 1st interosseous space. Activation of pain receptors induces prepulse inhibition of the blink reflex at a delay corresponding to a slowly conducting pathway. The percentage inhibition is similar to that observed with other somatosensory inputs.

Serum uric acid as a marker of microvascular damage in systemic sclerosis patients.

BACKGROUND Microvascular damage of skin and internal organs is a hallmark of systemic sclerosis (SSc). Serum uric acid (UA) represents a marker of inflammation and endothelial dysfunction. The aims of this study were to evaluate the correlation between serum UA and intrarenal arterial stiffness evaluated by Doppler ultrasound in SSc patients with normal renal function. We also evaluated the correlation between serum UA and other clinical variables of the disease. METHODS Forty-five SSc patients underwent clinical assessment, Doppler ultrasound of intrarenal arteries with evaluation of resistive index (RI), pulsatile index (PI), and systolic/diastolic ratio (S/D), echocardiography with systolic pulmonary artery pressure (PAPs), baseline pulmonary function tests, and nailfold videocapillaroscopy (NVC). In all patients serum UA was measured. RESULTS The serum UA showed a significant positive correlation with sCr (r=0.33, p<0.0001) and PAPs (r=0.38, p<0.01) >and negative correlation with CKD-EPI (r=-0.35, p<0.01). The mean value of serum UA increased with severity of NVC damage. Using this cut-off value of 4.7mg/dl, the mean value of Doppler indices of intrarenal stiffness is significantly different (p<0.05) in SSc patients with low normal or high normal serum UA. CONCLUSIONS Serum UA concentration is higher in patients with high microvascular damage than in patients with low microvascular damage. These preliminary data must be confirmed in large prospective studies.

Correlation between intrarenal arterial stiffness and exercise tolerance in systemic sclerosis patients without renal and cardiopulmonary impairment: The role of the microvascular damage

Correlation between intrarenal arterial stiffness and exercise tolerance in systemic sclerosis patients without renal and cardiopulmonary impairment: The role of the microvascular damage Antonietta Gigante ⁎, Antonella Romaniello , Damiano Magri , Matteo Bonini , Biagio Barbano , Liborio Sardo , Silvia Quarta , Maria Anna Digiulio , Marcello Di Paolo , Rosario Cianci , Paolo Palange , Antonio Amoroso , Edoardo Rosato a

Pulmonary hypertension and clinical correlates in hypertrophic cardiomyopathy

BACKGROUND Pulmonary hypertension (PH) in patients with hypertrophic cardiomyopathy (HCM) has been investigated in a small number of studies. Purpose of this study was to assess the prevalence and its association with outcome in a population of consecutive HCM outpatients. METHODS We retrospectively analyzed data of 361 consecutive HCM outpatients in whom echocardiographic measurements of pulmonary artery systolic pressure (PASP) were available at initial and most recent evaluation. Four different clinical groups were specifically investigated: patients without left ventricular outflow tract obstruction (group A, 165), with obstruction (group B, 126), patients diagnosed at the age≥65 (group C, 50) and patients with end stage (ES) HCM (group D, 20). RESULTS PH was identified in 41 (11.4%) of the 361 patients at initial evaluation while it has been recognized in 25 (7,8% [1.1%/year]) during a median follow-up of 3.4years. Analysis of subgroups showed that prevalence of PH increased from patient group A to D (8%, group A, 19%, group B, 28% group C, 70%, group D, respectively, p<0,01). During follow-up, patients with PH showed a significant higher HCM-related mortality (p=0.01) and morbidity (p<0.001) as compared with those without PH, but in multivariable analysis, PH resulted an independent risk factor only for HCM-related morbidity (HR=2.50, 95% CI 1.08-5.79, p=0.03). CONCLUSION PH affects a significant proportion of patients with HCM. Its prevalence varies according to different clinical profiles. It is associated with an unfavorable clinical outcome and is an independent predictor of morbidity.

The cardiac magnetic resonance in the diagnosis of cardiac Raynaud phenomenon in a patient with systemic sclerosis: case report and review of literature

ABSTRACT Raynaud phenomenon (RP) is the hallmark of Systemic Sclerosis (SSc). Visceral RP has also been proposed in SSc patients. Cardiac Raynaud’s phenomenon (C-RP) was evaluated in a few clinical studies both as cold-induced transient myocardial ischaemia and as presence of advanced myocardial fibrosis and contraction band necrosis in autopsied patients. Until today numerous techniques, such as scintigraphy and myocardial contrast echocardiography, have been used to evaluate C-RP. In this case report for the first time we have used Cardiac Magnetic Resonance (CMR) after cold test to demonstrate the presence of the C-RP. In addition we have shown that therapy with Iloprost can be used to reduce episodes of C-RP.

Laser evoked potentials and carbamazepine in epileptic patients

AIMS OF THE STUDY Nerve conduction studies have demonstrated that carbamazepine (CBZ), as well as other antiepileptic drugs (AEDs), can affect peripheral nerve conduction; reports on conventional somatosensory evoked potentials and CBZ are controversial. In a previous study, assessing laser-evoked potentials (LEPs) in CBZ-treated patients with idiopathic trigeminal neuralgia, we found that LEPs were dampened even after stimulation of the non-painful side, with a strong correlation between LEP latency and daily CBZ dose. No other study investigated the influence of AEDs on LEPs. In order to clarify the effect of CBZ on LEPs we sought possible LEP changes in epileptic patients taking CBZ. MATERIALS AND METHODS We studied LEPs after trigeminal and hand CO(2)-laser stimulation in 20 patients with epilepsy taking CBZ and 20 age-matched controls. RESULTS Although the trigeminal LEP mean latency was slightly longer in epileptic patients (P=0.11), we did not find significant differences between epileptic patients and controls for any LEP data. LEP data did not correlate with the daily CBZ dose, CBZ blood concentration, or duration of therapy (P>0.3). CONCLUSION The lack of a CBZ-induced dampening of LEPs suggests that small-fibre pathways, compared to large-fibre, might be less susceptible to AEDs toxic effect. Although the TN patients in our previous study were older than the epileptic patients in the present study, a possible combined effect induced by drug and age in patients with TN is unlikely because LEP latency is reportedly unaffected by age. The CBZ-induced effect in patients with trigeminal neuralgia is possibly related to pathophysiological changes specific to this disease.

Left ventricular mass and intrarenal arterial stiffness as early diagnostic markers in cardiorenal syndrome type 5 due to systemic sclerosis

Background: Cardiorenal syndrome type 5 (CRS-5) includes a group of conditions characterized by a simultaneous involvement of the heart and kidney in the course of a systemic disease. Systemic sclerosis (SSc) is frequently involved in the etiology of acute and chronic CRS-5 among connective tissue diseases. In SSc patients, left ventricular mass (LVM) can be used as a marker of nutritional status and fibrosis, while altered intrarenal hemodynamic parameters are suggestive of early kidney involvement. Methods: Forty-two consecutive patients with a diagnosis of SSc without cardiac and/or renal impairment were enrolled to assess whether cardiac muscle mass can be related to arterial stiffness. Thirty subjects matched for age and sex were also enrolled as healthy controls (HC). All patients performed echocardiography and renal ultrasound. Results: Doppler indices of intrarenal stiffness and echocardiographic indices of LVM were significantly increased in SSc patients compared to HC. A positive correlation exists between LVM/body surface area and pulsatile index (p < 0.05, r = 0.36), resistive index (p < 0.05, r = 0.33) and systolic/diastolic ratio (p < 0.05, r = 0.38). Doppler indices of intrarenal stiffness and LVM indices were significantly higher in SSc patients with digital ulcers than in SSc patients without a digital ulcer history. Conclusions: SSc is characterized by the presence of microvascular and multiorgan injury. An early cardiac and renal impairment is very common. LVM and intrarenal arterial stiffness can be considered as early markers of CRS onset. The clinical use of these markers permits a prompt identification of organ damage. An early diagnosis allows the appropriate setting of pharmacological management, by slowing disease progression.