Microcirculatory Impairment in Patients With Leprosy
Condition: Lepromatous Leprosy
MeSH terms: Leprosy; Leprosy, Lepromatous
Study type: Interventional

Summary: 
      In this study the investigators have aimed to evaluate morphology and reactivity of cutaneous
      microcirculation in patients with lepromatous leprosy. Ten patients, without any other
      comorbidity were compared to ten controls without leprosy or any other comorbidity, using the
      Cytoscan® [orthogonal polarization spectral (OPS) imaging], Fourier analysis of laser Doppler
      signal to evaluate vasomotion (rhythmic spontaneous oscillation of arteriolar diameter) and
      laser Doppler flowmetry associated to iontophoresis of vasoactive substances (acetylcholine
      and sodium nitroprusside).
    

Detailed description: 
      Evaluation with OPS:

      After acclimatization, the microcirculation of patients and controls was assessed by OPS in
      three different points, according to criteria recommended by De Backer(De Backer et al.,
      2007). Images were recorded for 10 seconds at each point and evaluated afterwards using
      Cap-Image v7.2software.

      Evaluation with laser-Doppler flowmetry (LDF):

      Skin blood perfusion was measured in conventional perfusion units (PU) by means of a LDF
      apparatus (Periflux PF4, Perimed, Stockholm, Sweden), equipped with a non-heated probe
      (PF408), fixed to the medial surface of the right forearm. Laser characteristics were: 780 nm
      wavelength, 10-19 kHz bandwidth, 0.1 s time constant and 32 Hz sampling frequency. Skin blood
      perfusion was expressed in conventional perfusion units (PU: 1 PU=10 mV) and LD signal was
      recorded continuously by an interfaced computer (Sony VaioVGN-CR160A) equipped with Perisoft
      dedicated software. Exams were performed in two steps:

      First, to register vasomotion, a probe (Probe 481-1: Single Iontophoresis Probe - Perimed,
      Stockholm, Sweden) was placed, after the skin was cleaned with a wipe of 70° alcohol and left
      to air dry, in the dorsal face of the distal phalanx of the 2nd finger. The probes were
      positioned at least 10 cm apart, avoiding superficial veins and broken skin areas. This probe
      may be used for both vasomotion and iontophoresis. Basal blood perfusion was continuously
      recorded during 20 min. Skin temperature was continuously measured.

      To avoid residual effects of previously used drugs, the probe position for combined
      iontophoresis and LDF recordings were placed in untreated fingers [2nd for acetylcholine
      (Ach) and 3nd for sodium nitroprusside (SNP)] after each measurement .

      Using a protocol similar to the one developed by Rossi and co-workers (Rossi et al., 2008),
      ACh (Acetylcholine - Sigma-Aldrich, St. Louis, USA) was delivered by 9 iontophoretic pulses
      of 0.1 mA for 20 s with 60 s interval between pulses using a drug delivery electrode filled
      with 0.1 ml of 1% ACh solution, attached to the dorsal aspect of the second left finger by a
      double-sided adhesive disc. After Ach, SNP (Nipride® 10mg/ml - Biolab, São Paulo, Brazil) was
      delivered by 7 iontophoretic pulses of 0.2 mA for 20 s with 180 s interval between pulses
      using another drug delivery electrode filled with 0.1 ml of 1% SNP solution, attached to the
      dorsal aspect of the third left finger. In both situations, an indifferent electrode was
      attached on the dorsal aspect of the left hand. Endothelial-dependent and independent skin
      vasodilator response to each iontophoresis pulse was measured in PUs, as mean value during
      each interval from one pulse to the following one.
    

Intervention name(s): acetylcholine Iontophoresis; sodium nitroprusside Iontophoresis
Intervention type(s): Drug; Drug
Intervention description(s): Using a protocol similar to the one developed by Rossi and co-workers (Rossi et al., 2008), ACh (Acetylcholine - Sigma-Aldrich, St. Louis, USA) was delivered by 9 iontophoretic pulses of 0.1 mA for 20 s with 60 s interval between pulses using a drug delivery electrode filled with 0.1 ml of 1% ACh solution, attached to the dorsal aspect of the second left finger by a double-sided adhesive disc.; After Ach, SNP (Nipride® 10mg/ml - Biolab, São Paulo, Brazil) was delivered by 7 iontophoretic pulses of 0.2 mA for 20 s with 180 s interval between pulses using another drug delivery electrode filled with 0.1 ml of 1% SNP solution, attached to the dorsal aspect of the third left finger. In both situations, an indifferent electrode was attached on the dorsal aspect of the left hand. Endothelial-dependent and independent skin vasodilator response to each iontophoresis pulse was measured in PUs, as mean value during each interval from one pulse to the following one.
Intervention MeSH terms: Nitroprusside; Acetylcholine
Allocation: Non-Randomized
Intervention model: Parallel Assignment
Masking: None (Open Label)
Primary purpose: Basic Science
Keywords: Microcirculation; Leprosy; Nervous system; Orthogonal polarization spectral (OPS) imaging; Laser Doppler flowmetry; Iontophoresis.