Morphological Differentiation of Corneal Inflammatory Cells: Proposal of Pragmatic Protocol

PURPOSE

Corneal confocal microscopy is a noninvasive imaging technique to analyze corneal nerve fibers and corneal inflammatory cells (CICs). The amount of CICs is a potential biomarker of disease activity in chronic autoinflammatory diseases. To date, there are no standardized criteria for the morphological characterization of CICs. The aim was to establish a protocol for a standardized morphological classification of CICs based on a literature search and to test this protocol for applicability and reliability.

METHODS

A systematic review of the literature about definitions of CICs was conducted. Existing morphological descriptions were translated into a structured algorithm and applied by raters. Subsequently, the protocol was optimized by reducing and defining the criteria of the cell types. The optimized algorithm was applied by 4 raters. The interrater reliability was calculated using Fleiss kappa (K).

RESULTS

A systematic review of the literature revealed no uniform morphological criteria for the differentiation of the individual cell types in CICs. Our first protocol achieved only a low level of agreement between 3 raters (K = 0.09; 1062 rated cells). Our revised protocol was able to achieve a higher interrater reliability with 3 (K = 0.64; 471 rated cells) and 4 (K = 0.61; 628 rated cells) raters.

CONCLUSIONS

The indirect use of criteria from the literature leads to a high error rate. By clearly defining the individual cell types and standardizing the protocol, reproducible results were obtained, allowing the introduction of this protocol for the future evaluation of CICs in the corneal confocal microscopy.

Association of the neonatal Fc receptor promoter variable number of tandem repeat polymorphism with immunoglobulin response in patients with chronic inflammatory demyelinating polyneuropathy

BACKGROUND AND PURPOSE

Chronic inflammatory demyelinating polyneuropathy (CIDP) is an autoimmune disease with humoral and cellular autoimmunity causing demyelination of peripheral nerves, commonly treated with intravenous immunoglobulins (IVIg). The neonatal Fc receptor (FcRn), encoded by the FCGRT gene, prevents the degradation of immunoglobulin G (IgG) by recycling circulating IgG. A variable number of tandem repeat (VNTR) polymorphism in the promoter region of the FCGRT gene is associated with different expression levels of mRNA and protein. Thus, patients with genotypes associated with relatively low FcRn expression may show a poorer treatment response to IVIg due to increased IVIg degradation.

METHODS

VNTR genotypes were analyzed in 144 patients with CIDP. Patients' clinical data, including neurological scores and treatment data, were collected as part of the Immune-Mediated Neuropathies Biobank registry.

RESULTS

Most patients (n = 124, 86%) were VNTR 3/3 homozygotes, and 20 patients (14%) were VNTR 2/3 heterozygotes. Both VNTR 3/3 and VNTR 2/3 genotype groups showed no difference in clinical disability and immunoglobulin dosage. However, patients with a VNTR 2 allele were more likely to receive subcutaneous immunoglobulins (SCIg) than patients homozygous for the VNTR 3 allele (25% vs. 9.7%, p = 0.02) and were more likely to receive second-line therapy (75% vs. 54%, p = 0.05).

CONCLUSIONS

The VNTR 2/3 genotype is associated with the administration of SCIg, possibly reflecting a greater benefit from SCIg due to more constant immunoglobulin levels without lower IVIg levels between the treatment circles. Also, the greater need for second-line treatment in VNTR 2/3 patients could be an indirect sign of a lower response to immunoglobulins.

The impact of the SARS-CoV-2-pandemic on patients with chronic inflammatory neuropathies: results from the German INHIBIT register

INTRODUCTION

SARS-CoV-2 pandemic is especially compromising for patients with autoimmune diseases with or without immunomodulatory treatment. This study aimed to investigate the longitudinal changes in the health care of patients with immune-mediated neuropathies during the COVID-19 pandemic.

METHODS

We performed a longitudinal study using questionnaires in a prospective cohort of patients with immune-mediated neuropathies at two timepoints of the pandemic: May-July 2021 and May-July 2022.

RESULTS

The cohort consisted of 73 patients (55 male), mean age 62 years, 68 patients with CIDP, 5 with other immune neuropathies. In 2021, 19.2% of the patients reported a reduced number of physician-patient-contacts, while 13.7% reported this in 2022. Nevertheless, the overall health-care situation worsened from 2021 to 2022: 15.1% reported reduced overall healthcare in 2021, 26.0% in 2022. In 2021, 29.4% of patients reported absence of physio-/occupational therapy, while 34.4% reported this in 2022. Switching immunomodulatory treatment and stretching of treatment intervals occurred more often in 2022 (38.4%) than in 2021 (27.4%). 12 COVID-19-infections occurred overall, with typical only mild symptoms. The rate of fully vaccinated patients was 61.6% and 98.6% in May-July 2021 and 2022, respectively. Only minor side-effects after vaccination were reported.

CONCLUSION

Despite mitigation of COVID-19 restrictions from 2021 to 2022, the health-care situation of patients worsened in this time. Reasons could be the international shortage of immunoglobulins during the pandemic and reduced physio/ergotherapy due to lingering regulatory restrictions. Vaccination rate was high in our cohort of patients compared to the general German population and CIDP did not seem to be a risk factor for severe SARS-CoV-2 infections.

Vagal cross-sectional area correlates with parasympathetic dysfunction in Parkinson's disease

The aim of this prospective study was to investigate autonomic function in Parkinson's disease with a multidimensional approach including clinical evaluation tools, head-up tilt test and morphological studies of the vagus nerve. Head-up tilt test parameters including high frequency power of the heart frequency interval, the ratio of low frequency power of the distance between two consecutive R waves in electrocardiogram (RR interval) to the high frequency and low frequency power of systolic blood pressure were used to evaluate parasympathetic, cardiac sympathetic and vasomotor sympathetic functions, respectively, in 80 patients with Parkinson's disease. We examined the cross-sectional area of the vagus nerves bilaterally using nerve ultrasound and compared mean values with a control group of healthy subjects (n = 40) as well as patients with chronic inflammatory demyelinating polyneuropathy (n = 76). The cross-sectional area of right/left vagus nerve of Parkinson's patients was significantly lower compared to the right/left vagus nerve of the control group and of chronic demyelinating polyneuropathy patients. Furthermore, the cross-sectional area of the right vagus nerve was significantly larger from the one of the left vagus nerve for all groups. Based on tilt test, 43 patients (disease duration 7 ± 5, age at evaluation 71 ± 9, Hoehn and Yahr score 2.8 ± 8) were diagnosed with autonomic dysfunction (orthostatic hypertension n = 11, chronotropic incompetence n = 31, postural orthostatic tachycardia syndrome n = 1). Patients with orthostatic hypotension showed significantly higher Unified Parkinson's Disease Rating Scale-III values than those with chronotropic incompetence. The cross-sectional area of the vagus nerve correlated inversely with heart rate in rest and supine position and positively with tilt test parameters representing parasympathetic modulation through vagal activity [high frequency power of the distance between two consecutive R waves in electrocardiogram (RR interval)] at rest. We demonstrate for the first time that morphological characteristics of the vagus nerve correlate with parameters of parasympathetic function from the spectral analysis of cardiovascular parameters in tilt test for Parkinson's patients. This correlation reveals the impact of the atrophy of vagal atrophy for autonomic function in Parkinson's disease. Nerve ultrasound of the vagus nerve could potentially be used as an adjunct to tilt table examination to diagnose autonomic dysfunction.

Prevalence and determinants of pain in chronic inflammatory demyelinating polyneuropathy: results from the German INHIBIT registry

INTRODUCTION

Pain, fatigue and depression in chronic inflammatory demyelinating polyneuropathy (CIDP) are often underestimated, as the focus lies on sensorimotor dysfunction and gait instability. The aim of this study was to investigate their prevalence, characteristics and contribution to disability in a prospective cohort of 84 patients with CIDP.

METHODS

Pain, fatigue, depression and quality of life were measured using Pain Detect Questionnaire, Krupp's Fatigue Severity Scale, Beck Depression Inventory-II and German Short-Form-36 Health Survey. Sensorimotor deficits and disability were assessed using the Inflammatory Neuropathy Cause and Treatment overall disability score, the Rasch-built Overall Disability Scale, the Medical Research Council Sum Score and the INCAT-sensory sum-score. The interrelation between the five factors was assessed using analysis of variance and linear regression analysis.

RESULTS

Pain was reported in 62%, mostly of moderate and severe intensity, whereas pain characteristics indicated of neuropathic pain (NP) in 29%. Sensory dysfunction was stronger in NP-patients compared to pain-free patients (p=0.001). Pain of any type, especially NP, was associated with more pronounced fatigue symptoms (p=0.010). Depressive symptoms were more frequent in patients with pain compared to the pain-free patients (61% vs. 33%, p=0.02) and were more severe and frequent in NP-patients than in non-NP (p=0.005). Patients with pain had a worse physical quality of life than pain-free patients (p=0.001).

CONCLUSION

Pain, depression and fatigue are relevant disability factors in CIDP affecting quality of life. Sensory dysfunction is associated with NP. Therefore, evaluation of CIDP-related disability should include pain and sensory function for adequate monitoring of therapeutic interventions.

Nerve Ultrasound Distinguishes Non-Inflammatory Axonal Polyneuropathy From Inflammatory Polyneuropathy With Secondary Axonal Damage

Introduction

Chronic inflammatory demyelinating polyneuropathy (CIDP) may have a similar clinical and electrophysiological presentation to non-inflammatory axonal polyneuropathies (NIAPs) when secondary axonal damage occurs. We aimed to investigate if nerve ultrasound can help to differentiate CIDP with additional secondary axonal damage from NIAP.

Methods

In a retrospective analysis, the cross-sectional area (CSA) of the peripheral nerves measured by ultrasound at six suitable nerve sites was compared in 95 patients with CIDP and 82 patients with NIAP. We developed the adjusted Bochum ultrasound score (aBUS) ranging from 0 to 6 resulting from the number of sites with enlarged CSA (median, ulnar, radial, and sural nerve).

Results

The mean CSA of patients with CIDP was enlarged at all six nerve sites compared with the mean CSA of patients with NIAP. A total of 21 patients with CIDP did not meet 2010 electrophysiological diagnostic criteria (European Academy of Neurology/Peripheral Nerve Society Guideline, EFNS/PNS criteria) for CIDP at examination timepoint but only in further follow-up, while 25 patients with NIAP fulfilled electrophysiological EFNS/PNS criteria for CIDP as “possible” or “probable” CIDP. To increase diagnostic power, we included aBUS measured by ultrasound in patients classified as “possible” or “probable” resulting in an improved specificity of 94% and a sensitivity of 59%, compared to a specificity of the EFNS/PNS criteria alone of 60% and sensitivity of 78%.

Conclusion

Using nerve ultrasound and the aBUS as a complementary method to distinguish CIDP from NIAP in case of secondary axonal damage can facilitate the diagnosis of CIDP.

Increased muscle echointensity correlates with clinical disability and muscle strength in chronic inflammatory demyelinating polyneuropathy

BACKGROUND AND PURPOSE

We evaluated muscle echointensity as a marker for secondary axonal damage in patients with chronic inflammatory demyelinating polyneuropathy (CIDP) using ultrasonography. Findings were correlated with clinical disability and muscular strength.

METHODS

Eighty patients with CIDP (40 with typical and 40 with atypical CIDP) were examined clinically, including assessment of Medical Research Council (MRC) sum score and Inflammatory Neuropathy Cause and Treatment Overall Disability Sum Score (INCAT-ODSS). Echointensity in eight proximal and distal muscles of the arms and legs was evaluated by muscle ultrasonography using the Heckmatt scale.

RESULTS

Alterations of echointensity occurred most frequently in the distal leg muscles, with a median (range) Heckmatt score of 1.5 (1-4). There were no differences between typical and atypical CIDP patients with regard to Heckmatt score. Alterations of echointensity correlated to disability and muscle strength. The arm score of the INCAT-ODSS correlated to Heckmatt score for the distal arm muscles (r = 0.23, p = 0.046) and the leg score of the INCAT-ODSS correlated to Heckmatt scores for the proximal (r = 0.34, p = 0.002) and distal leg muscles (r = 0.33, p = 0.004). MRC sum score, as well as individual MRC scores for arm and leg muscles, correlated to Heckmatt scores of the corresponding muscle groups (r = -0.25, p = 0.02 for MRC sum score).

CONCLUSION

Increased muscle echointensity, reflecting fibrosis and fatty infiltration due to secondary axonal damage, correlated to muscular strength and disability in a large cohort of CIDP patients. Alterations of echointensity occur in both typical and atypical CIDP patients and are pronounced in the distal leg muscles.

[Exogenous allergic alveolitis during childhood (author's transl)]

Four children aged 31/2 to 13 years, who developed allergic alveolitis as a result of antigenic exposure in a domestic situation are described. The clinical symptoms consisted of gradual onset of increasing dyspnoea, chronic cough and weight loss. Lung function tests showed characteristic reduction in vital and diffusion capacity. Serologically, antibodies against animal antigens were demonstrated in all patients. Radiologically there were pronounced reticular changes in both lungs affecting mostly the middle and lower zones. Occasionally there were miliary and sometimes confluent shadows. In differential diagnosis, virus infections, pneumocystis carinii, fungus infections, dermatomyositis, sarcoidosis and tuberculosis had to be considered. Apart from a short course of steroid treatment, it is necessary to make certain that the children are no longer exposed to the causal antigen. Under these conditions the prognosis is good, but otherwise the disease, as in adults who are continuously exposed to the antigen, results in pulmonary fibrosis.

[Indication and examination technique of voiding cystourethrography in children (author's transl)]

Roentgen diagnosis in children with urological disease are of special interest in pediatric radiology. These examinations are more frequent than those of the gastrointestinal tract. Voiding cystourethrography is an important diagnostic procedure in chronic relapsing urinary infections. Indications and performance of voiding cystourethrographies in children is described. All precautions reducing x-ray exposure have to be taken into consideration. New technical standards enhance higher accuracy in diagnosis at lowest x-ray exposure to the patients.