Retrospective study of the incidence of sarcoidosis-like reaction in patients treated with immunotherapy

AIM

To assess the frequency of radiographically evident drug-induced sarcoidosis-like reaction (DISR) in patients treated with anti-cytotoxic T-lymphocyte-associated antigen-4 (CTLA-4) therapy, anti-programmed cell death protein 1 (PD-1) therapy, or a combination of both in a single centre.

MATERIALS AND METHODS

The images and medical records of 457 patients with metastatic melanoma or head and neck cancer treated with either anti-CTLA-4 therapy, anti-PD-1 therapy, or a combination of both at University of California medical centre were reviewed retrospectively and the incidence of radiological manifestations of DISR was assessed among these treatment groups.

RESULTS

Radiological manifestations of DISR were found in 19/457 patients (4.1%). The mean interval from the initiation of immunotherapy to development of DISR was 5.5 months (range 2.3-13.5 months). Mean interval from radiological detection of DISR to imaging evidence of resolution was 5.8 months (range 1.6-18.3 months). Three patients out of 81 (3.7%), 11/297 (3.7%), and 5/79 (6.3%) developed sarcoidosis-like reaction after treatment with anti-CTLA-4 antibody, anti-PD-1 antibody, and a combination of both, respectively. Most patients with DISR were asymptomatic and did not require systemic therapy. Most patients did not demonstrate concomitant increased maximum standardised uptake value (SUVmax) in other organs on their integrated 2-[¹⁸F]-fluoro-2-deoxy-d-glucose (FDG) positron-emission tomography (PET)/computed tomography (CT).

CONCLUSIONS

In the present retrospective study of patients treated with immune checkpoint inhibitors (ICIs), DISR occurred in approximately 3.7% of patients treated with either anti-CTLA-4 or anti-PD-1 antibody and 6.3% of patients treated with a combination of both.

Analysis of the effectiveness of training school personnel in the management of food allergy and anaphylaxis

BACKGROUND

Food allergy is a very frequent and increasingly common disease in children and adolescents. It affects quality of life and can even be life-threatening. Given that 10-18% of allergic/anaphylactic food reactions take place in schools, it is essential to provide school personnel with training on the management of reactions.

METHODS

The Allergy Unit of Hospital Universitario de Fuenlabrada, Spain, organized a conference entitled "Management of Food Allergy in Children and Adolescents in School Centers" during which teachers, cooks, cafeteria monitors, and summer-camp leaders underwent a training course. Attendees filled out a questionnaire with eight questions before and after the course to assess their self-efficacy in management of food allergy and anaphylaxis. The results were compared.

RESULTS

A total of 191 people participated (51% dining-room monitors, 24% teachers, 13% cooks, and 12% other professions). The areas in which the attendees presented the lowest confidence before receiving the course were recognition of symptoms and treatment of the reactions/anaphylaxis. The mean score for each of the eight concepts evaluated improved after the training course. This improvement was significant in the management of anaphylaxis.

CONCLUSIONS

Our study demonstrates the usefulness of a self-efficacy scale in school personnel as a tool to assess the ability to manage food allergy and anaphylaxis. It can help to identify problem areas in which more specific training programs can be implemented.

Elucidating nonlinear baroreflex and respiratory contributions to heart rate variability in obstructive sleep apnea syndrome

Using a Volterra-Wiener model and the Laguerre expansion technique, we estimated in a previous study the parameters that characterize linear and the second order effects of respiration ("RSA") and arterial blood pressure ("ABR") on heart rate. RSA and ABR gains were significantly lower in Obstructive Sleep Apnea (OSA) patients than in normal subjects. During sleep, ABR gain increased in normals but remained unchanged in OSA. In the present work, we investigated the physiological interpretation of the nonlinear components of the described model of heart rate variability, by means of simulation on the computed linear and nonlinear kernels. Our results indicate that the 2^ndorder kernels reflect specific characteristics of the RSA and ABR mechanisms, such as a RSA frequency response dependence upon tidal volume, saturation in the ABR-Blood Pressure relation, and respiratory modulation of ABR.

Closed-loop minimal model analysis of the cardiovascular response to transient arousal from sleep in healthy humans

In a previous work we reported discrepancies in the cardiovascular response to arousal from NREM sleep between OSAS patients and healthy controls. The long lasting cardiac sympathetic increase observed in normals was not present in the OSAS group, whereas the peripheral vasculature reaction was similar between the two groups. Analysis of REM arousal revealed that there was a similar temporary cardiac sympathetic impairment in the control group. In this work we have implemented a model-based time domain system identification method to assess the mechanisms involved in this reaction to arousal from both NREM and REM sleep in a group of healthy subjects. The use of time-varying techniques has enabled us to characterize the arousal reaction by analyzing the change in shape of the impulse responses of the system. The mechanisms regulating respiration and vascular effects on heart rate (respiratory sinus arrhythmia or RSA and arterial baroreflex or ABR, respectively) were the most affected by NREM arousal, likely as a result of the return of the wakefulness stimulus. The effect observed on the cardiac influence on the vasculature (circulatory dynamics, CID) was attributed to a change in the dominant mechanism prevailing in its dynamics.

Determinants of heart rate variability in obstructive sleep apnea syndrome during wakefulness and sleep

Heart rate variability (HRV) is mediated by at least three primary mechanisms: 1) vagal feedback from pulmonary stretch receptors (PSR), 2) central medullary coupling between respiratory and cardiovagal neurons (RCC), and 3) arterial baroreflex (ABR)-induced fluctuations. We employed a noninvasive experimental protocol in conjunction with a minimal model to determine how these sources of HRV are altered in obstructive sleep apnea syndrome (OSAS). Respiration, heart rate, and blood pressure were monitored in eight normal subjects and nine untreated OSAS patients in relaxed wakefulness and stage 2 and rapid eye movement sleep. A computer-controlled ventilator delivered inspiratory pressures that varied randomly from breath to breath. Application of the model to the corresponding subject responses allowed the delineation of the three components of HRV. In all states, RCC gain was lower in OSAS patients than in normal subjects (P < 0.04). ABR gain was also reduced in OSAS patients (P < 0.03). RCC and ABR gains increased from wakefulness to sleep (P < 0.04). However, there was no difference in PSR gain between subject groups or across states. The findings of this study suggest that the adverse autonomic effects of OSAS include impairment of baroreflex gain and central respiratory-cardiovascular coupling, but the component of respiratory sinus arrhythmia that is mediated by lung vagal feedback remains intact.

Ventilatory responses to acute and chronic hypoxia in mice: effects of dopamine D(2) receptors

We used genetically engineered D(2) receptor-deficient [D(2)-(-/-)] and wild-type [D(2)-(+/+)] mice to test the hypothesis that dopamine D(2) receptors modulate the ventilatory response to acute hypoxia [hypoxic ventilatory response (HVR)] and hypercapnia [hypercapnic ventilatory response (HCVR)] and time-dependent changes in ventilation during chronic hypoxia. HVR was independent of gender in D(2)-(+/+) mice and significantly greater in D(2)-(-/-) than in D(2)-(+/+) female mice. HCVR was significantly greater in female D(2)-(+/+) mice than in male D(2)-(+/+) and was greater in D(2)-(-/-) male mice than in D(2)-(+/+) male mice. Exposure to hypoxia for 2-8 days was studied in male mice only. D(2)-(+/+) mice showed time-dependent increases in "baseline" ventilation (inspired PO(2) = 214 Torr) and hypoxic stimulated ventilation (inspired PO(2) = 70 Torr) after 8 days of acclimatization to hypoxia, but D(2)-(-/-) mice did not. Hence, dopamine D(2) receptors modulate the acute HVR and HCVR in mice in a gender-specific manner and contribute to time-dependent changes in ventilation and the acute HVR during acclimatization to hypoxia.