Purpose Interstitial cystitis (IC) is a highly prevalent pain condition, estimated to affect 3-6% of women in the United States. Emerging data suggests there are central neurobiological components to the etiology of this disease. Here we report the first brain structural imaging findings from the Multidisciplinary Approach to Pelvic Pain (MAPP) network, with data on over 300 participants. Materials and Methods We used Voxel-Based Morphometry (VBM) to determine whether human patients with chronic IC display changes in brain morphology as compared to healthy controls (HCs). 33 female IC patients without comorbidities and 33 age- and sex-matched controls, taken from the larger sample, underwent structural magnetic resonance imaging at 5 different MAPP sites across the United States. Results When compared to controls, females with IC displayed significant increased gray matter (GM) volume in several regions of the brain including the right primary somatosensory cortex (S1), the superior parietal lobule bilaterally, and the right supplementary motor area. GM volume in the right S1 was associated with greater pain, mood (anxiety), and urological symptoms. We explored these correlations in a linear regression model and found independent effects of these three measures on S1 GM volume: clinical pain (McGill pain sensory total), a measure of “urgency,” and anxiety (HADS). Conclusions These data support the notion that changes in somatosensory GM may play an important role in pain sensitivity as well as affective and sensory aspects of IC. Further studies are needed to confirm the generalizability of these findings to other pain conditions.

Background: Fibromyalgia is a chronic widespread pain condition, with patients commonly reporting other symptoms such as sleep difficulties, memory complaints and fatigue. The use of magnetic resonance imaging (MRI) in fibromyalgia has allowed for the detection of neural abnormalities, with alterations in brain activation elicited by experimental pain and alterations in resting state connectivity related to clinical pain. Methods: In this study, we sought to monitor state changes in resting brain connectivity following experimental pressure pain in fibromyalgia patients and healthy controls. Twelve fibromyalgia patients and 15 healthy controls were studied by applying discrete pressure stimuli to the thumbnail bed during MRI. Resting-state functional MRI scanning was performed before and immediately following experimental pressure pain. We investigated changes in functional connectivity to the thalamus and the insular cortex. Results: Acute pressure pain increased insula connectivity to the anterior cingulate and the hippocampus. Additionally, we observed increased thalamic connectivity to the precuneus/posterior cingulate cortex, a known part of the default mode network, in patients but not in controls. This connectivity was correlated with changes in clinical pain. Conclusions: These data reporting changes in resting-state brain activity following a noxious stimulus suggest that the acute painful stimuli may contribute to the alteration of the neural signature of chronic pain. What does this study/add?: In this study acute pain application shows an echo in functional connectivity and clinical pain changes in chronic pain.

Until recently, the predominant pathology of chronic pelvic pain conditions was thought to reside in the peripheral tissues. However, mounting evidence from neuroimaging studies suggests an important role of the central nervous system in the pathogenesis of these conditions. In the present cross-sectional study, proton magnetic resonance spectroscopy (1H-MRS) of the brain was conducted in female patients with urologic chronic pelvic pain syndrome (UCPPS) to determine if they exhibit abnormal concentrations of brain metabolites (e.g. those indicative of heightened excitatory tone) in regions involved in the processing and modulation of pain, including the anterior cingulate cortex (ACC) and the anterior and posterior insular cortices. Compared to a group of age-matched healthy subjects, there were significantly higher levels of choline (p = 0.006, uncorrected) in the ACC of UCPPS patients. ACC choline levels were therefore compared with the region's resting functional connectivity to the rest of the brain. Higher choline was associated with greater ACC-to-limbic system connectivity in UCPPS patients, contrasted with lower connectivity in controls (i.e. an interaction). In patients, ACC choline levels were also positively correlated with negative mood. ACC γ-aminobutyric acid (GABA) levels were lower in UCPPS patients compared with controls (p = 0.02, uncorrected), but this did not meet statistical correction for the 4 separate regional comparisons of metabolites. These results are the first to uncover abnormal GABA and choline levels in the brain of UCPPS patients compared to controls. Low GABA levels have been identified in other pain syndromes and might contribute to CNS hyper-excitability in these conditions. The relationships between increased ACC choline levels, ACC-to-limbic connectivity, and negative mood in UCPPS patients suggest that this metabolite could be related to the affective symptomatology of this syndrome.

Immune checkpoint inhibitors are increasingly being used in the treatment of various solid organ and hematologic malignancies. Dermatologic toxicities associated with programmed cell death protein-1 (PD-1) and programmed death ligand-1 (PD-L1) therapy have been widely reported in the literature. It is important for clinicians to be aware of these toxicities to ensure prompt recognition and treatment. Herein, we present the clinical, histopathologic, and immunofluorescence findings of 3 patients diagnosed with lichen planus pemphigoides (LPP) after treatment with anti-PD-1 inhibitors. We also reviewed the literature and summarize 7 previously reported cases of LPP associated with anti-PD-1 and anti-PD-L1 inhibitors. LPP was diagnosed at a median time of 24.4 weeks (range: 4-78 weeks) after initiation of immunotherapy. Clinical findings included papules, plaques, erosions, vesicles, and bullae on the trunk and extremities. Oral involvement was present in half the cases. Histopathologic features of immunotherapy-induced LPP included lichenoid or vacuolar interface dermatitis, the presence of eosinophils, and subepidermal bullae. Direct immunofluorescence demonstrated linear deposition of immunoglobulin G (IgG) or C3. Indirect immunofluorescence demonstrated linear IgG along basement membrane zone on monkey esophagus in 2 cases and linear IgG on the epidermal side of salt split skin in 3 cases. Serum anti-BP180 was elevated in all cases in which enzyme-linked immunosorbent assay was performed.

Objective; Pregabalin (PGB) is an α2β calcium channel subunit ligand that has previously been shown to reduce chronic pain in multiple conditions. Preclinical studies indicate that PGB may down-regulate brain glutamate release while also inhibiting astrocyte induction of glutamatergic synapse formation. Recent clinical research supports PGB modulating glutamatergic activity and functional brain connectivity in order to produce analgesia. However, no studies have examined concurrent changes in brain gray matter volume (GMV) or evoked-pain connectivity in humans receiving PGB. Methods Sixteen female fibromyalgia patients completed a randomized double-blind two-period cross-over study of PGB versus placebo (PBO). Before and after each period, patients had high-resolution structural and evoked pressure-pain functional brain imaging. GMV was analyzed using voxel-based morphometry, and functional connectivity during evoked pressure-pain was also assessed. Results PGB administration significantly reduced GMV within the posterior insula bilaterally, whereas there were no significant changes in insular GMV following PBO treatment. GMV reductions were also observed when comparing PGB versus PBO treatment in the medial frontal gyrus, which were associated with reduced clinical pain. These reductions in insular GMV were associated with concomitant reductions in connectivity to the default mode network (DMN), which was also associated with reduced clinical pain. Conclusion Short-term PGB treatment alters brain structure and evoked-pain connectivity, and these decreases were associated with reduced clinical pain. We speculate that these fairly rapid changes in GMV may be related to brain neuroplasticity. It is unknown if these effects are generalizable to other chronic pain states.