High-resolution ultrasonography for early diagnosis of neural impairment in seropositive leprosy household contacts

Abstract

Leprosy household contacts (HC) represent a high-risk group for the development of the disease. Anti-PGL-I IgM seropositivity also increases the risk of illness. Despite significant advances in leprosy control, it remains a public health problem; and early diagnosis of this peripheral neuropathy represents one of the main goals of leprosy programs. The present study was performed to identify neural impairment in leprosy HC by analyzing differences in high-resolution ultrasonographic (US) measurements of peripheral nerves between leprosy HC and healthy volunteers (HV). Seventy-nine seropositive household contacts (SPHC) and 30 seronegative household contacts (SNHC) underwent dermato-neurological examination and molecular analysis, followed by high-resolution US evaluation of cross-sectional areas (CSAs) of the median, ulnar, common fibular and tibial nerves. In addition, 53 HV underwent similar US measurements. The US evaluation detected neural thickening in 26.5% (13/49) of the SPHC and only in 3.3% (1/30) among the SNHC (p = 0.0038). The CSA values of the common fibular and tibial nerves were significantly higher in SPHC. This group also had significantly greater asymmetry in the common fibular and tibial nerves (proximal to the tunnel). SPHC presented a 10.5-fold higher chance of neural impairment (p = 0.0311). On the contrary, the presence of at least one scar from the BCG vaccine conferred 5.2-fold greater protection against neural involvement detected by US (p = 0.0184). Our findings demonstrated a higher prevalence of neural thickening in SPHC and support the role of high-resolution US in the early diagnosis of leprosy neuropathy. The combination of positive anti-PGL-I serology and absence of a BCG scar can identify individuals with greater chances of developing leprosy neuropathy, who should be referred for US examination, reinforcing the importance of including serological and imaging methods in the epidemiological surveillance of leprosy HC.

Neurological features of Hansen disease: a retrospective, multicenter cohort study

“…Nerve ultrasonography has been performed to assess peripheral nerves in patients with Hansen disease in multiple studies. A significant increase in the CSA of the ulnar, median, radial, common peroneal, and tibial nerves of Hansen disease patients has been mostly reported 22 – 29 . The sonographic findings of Hansen disease patients are characterized by an increased CSA and a pattern of asymmetry and focality of this thickening, with high sensitivity and specificity for early diagnosis 24 .…”

“…The risk factors for nerve enlargement in patients with Hansen disease were MB leprosy 25 , leprosy reaction 26 , neuritis 27 , and impairment of function 28 . Nerve ultrasonography for Hansen disease can be applied in the early diagnosis of Hansen disease in household contacts (HHCs) 29 and for monitoring the therapeutic effects of MDT 27 . Compared with healthy volunteers, individuals with at least two thickened nerves assessed in the active search campaign had a 23.1 greater chance of having Hansen disease than healthy individuals 24 .…”

Role of multisegmental nerve ultrasound in the diagnosis of leprosy neuropathy

“…The present study systematically evaluated the measurements of the peripheral nerves of upper and lower limbs in LPs assisted in a national reference center for leprosy in Brazil, using a multisegmental US method, and also investigated differences among their clinical forms according to the Ridley-Jopling classification. Several previous studies had already investigated measurements of the nerves in leprosy neuropathy by US [ 14 , 18 – 22 , 31 , 35 ], but this is one of the few studies available in the literature that simultaneously evaluated the median, ulnar and tibial nerves in a multisegmental technique [ 29 , 32 , 36 ].…”

“…As a comparative (control) sample of healthy Brazilian volunteers, we used the database of the radiology laboratory of our service, established by Luppi et al [ 32 ]. Considering that the US assessment of peripheral nerves is still a recent technique, we believe that internal standardization is important.…”

Immunopathogenesis of Type 1 and Type 2 Leprosy Reaction: An Update Review

“…This condition is defined by a cellular immune response targeted explicitly towards specific antigens of the M. leprae bacteria [1]. The distinguishing characteristic of T1LR is the sudden onset of acute inflammation in preexisting cutaneous lesions or the development of new lesions, sometimes accompanied by neuritis [2].…”