Predicting Delayed Shock in Multisystem Inflammatory Disease in Children: A Multicenter Analysis From the New York City Tri-State Region

OBJECTIVES

Patients with multisystem inflammatory disease in children (MIS-C) are at risk of developing shock. Our objectives were to determine independent predictors associated with development of delayed shock (≥3 hours from emergency department [ED] arrival) in patients with MIS-C and to derive a model predicting those at low risk for delayed shock.

METHODS

We conducted a retrospective cross-sectional study of 22 pediatric EDs in the New York City tri-state area. We included patients meeting World Health Organization criteria for MIS-C and presented April 1 to June 30, 2020. Our main outcomes were to determine the association between clinical and laboratory factors to the development of delayed shock and to derive a laboratory-based prediction model based on identified independent predictors.

RESULTS

Of 248 children with MIS-C, 87 (35%) had shock and 58 (66%) had delayed shock. A C-reactive protein (CRP) level greater than 20 mg/dL (adjusted odds ratio [aOR], 5.3; 95% confidence interval [CI], 2.4-12.1), lymphocyte percent less than 11% (aOR, 3.8; 95% CI, 1.7-8.6), and platelet count less than 220,000/uL (aOR, 4.2; 95% CI, 1.8-9.8) were independently associated with delayed shock. A prediction model including a CRP level less than 6 mg/dL, lymphocyte percent more than 20%, and platelet count more than 260,000/uL, categorized patients with MIS-C at low risk of developing delayed shock (sensitivity 93% [95% CI, 66-100], specificity 38% [95% CI, 22-55]).

CONCLUSIONS

Serum CRP, lymphocyte percent, and platelet count differentiated children at higher and lower risk for developing delayed shock. Use of these data can stratify the risk of progression to shock in patients with MIS-C, providing situational awareness and helping guide their level of care.

POS0466 RESISTANT STARCH DIET IMPROVES DISTINCT GUT MICROBIOTA STRUCTURES IN PATIENTS WITH SYSTEMIC LUPUS ERYTHEMATOSUS AND ANTIPHOSPHOLIPID SYNDROME

Background

Fiber-poor diets are linked to a reduction in gut microbiota diversity and gut barrier integrity, which is thought to promote the susceptibility to chronic inflammatory disorders1,2. We have previously shown that dietary resistant starch (RS) improves lupus-like disease in a murine model of SLE3 through the modulation of microbiota composition. If similar dysbiotic microbial community structures exist in subsets of SLE patients and if a RS intervention may be efficacious in those patients remains unclear.

Objectives

To test if the dietary RS content in SLE and SLE-related antiphospholipid syndrome (APS) affect gut microbial taxa associated with SLE in published cohorts to date.

Methods

We obtained stool and blood samples as well as diet history for up to 3 visits (0, 4 and 8 weeks) from 12 SLE (n=28) and 15 APS (n=44) patients as well as 20 controls (n=48) as previously published4-6. Microbiota composition was defined by 16S rRNA V4 region sequencing on the Illumina platform and correlated with dietary fiber content extracted from a diet questionnaire. We used the FDA reference list to determine dietary RS contents in patients` regular diets and defined RS quantities as being low if less than 2.5 g/day and as medium if 2.5 to 15 g/day. None of the patients achieved high RS greater than 15 g/day. Mann-Whitney or Kruskal-Wallis tests were performed to compare bacteria relative abundances among the different groups. Simple linear regression was performed to relate the bacterial abundance to RS content and other metadata.

Results

Medium intake of RS was associated with beneficial Bifidobacterium spp. in SLE patients (p=0.016) but not APS (p=0.509). Instead, APS patients who consumed medium quantities of RS in their diets had less gut bacterial taxa that are capable of producing cardiolipins (among them Collinsella; p=0.009) and Ruminococcus gnavus (p=0.0142), a species previously associated with lupus nephritis7. A recent Japanese metagenome-wide study8 associated Streptococcus spp. and related redox reaction genes with SLE, which may also affect oxidative processes in APS9. We therefore also explored Streptococcus levels in SLE and APS patients and found unexpectedly a significant reduction of streptococci in a subset of APS (p=0.004) but not SLE patients (p=0.451) in medium compared to low RS dietary content. Streptococcus abundance was correlated with both Collinsella (R2=0.3141; p=<0,0001) and Ruminococcus gnavus (R2=0.1687; p=<0,0056) in APS patients.

Conclusion

Medium compared to low RS quantities in the regular diets of SLE and APS patients were associated with unique alterations in gut microbial community structures. Bifidobacterium increased in SLE patients with diets containing medium RS whereas APS patients with medium RS carried less cardiolipin-synthesizing taxa and lupus-related pathobionts. In particular, Streptococcus species recently strongly associated with SLE and redox reactions in Japanese patients in a metagenome-wide study8, were significantly suppressed in APS patients on medium RS diets. This modulatory effect was not seen in SLE patients or control subjects consuming medium RS. Together, these findings support distinct dietary effects on autoimmune gut microbiomes depending on the disease state. They also suggest potential beneficial effects of increased RS content on gut microbiota in SLE and APS patients. Fully resolving gut microbial signatures and clinical characteristics in these patients may identify the ideal subset to benefit from an interventional pilot trial with RS.

References

[1] Thorburn et al., 2014, Immunity 19, 833-842

[2] Ruff et al, 2020, Nat Rev Microbiol 18, 521-538

[3] Zegarra-Ruiz et al., 2019, Cell Host Microbe 25, 113-127

[4] Greiling et al., 2018, Science Transl Med 10, 1–15

[5] Manfredo Vieira et al, 2018, Science 359, 1156-1161

[6] Ruff et al., 2019, Cell Host Microbe 26, 1–14

[7] Azzouz et al., 2019, Ann Rheum Dis 78, 947–956

[8] Tomofuji et al., 2021, Ann Rheum Dis 80, 1575–1583

[9] Giannakopoulos and Krilis, 2013, New Engl J Med 368, 1033-1044

Acknowledgements

The work was supported by grants from the National Institutes of Health (NIH) (R01AI118855, T32AI07019), Arthritis National Research Foundation, Arthritis Foundation, Lupus Research Alliance, and Maren Foundation.

Disclosure of Interests

Márcia Pereira: None declared, Iryna Kulyk: None declared, Sylvio Redanz: None declared, William E Ruff: None declared, Teri M. Greiling: None declared, Carina Dehner: None declared, Odelya Pagovich: None declared, Daniel Zegarra Ruiz: None declared, Cassyanne Aguiar: None declared, Doruk Erkan: None declared, Martin Kriegel Speakers bureau: Novartis, BMS, GSK, MSD, Grant/research support from: AbbVie, Employee of: Roche.

Short-Term Outcomes After Multisystem Inflammatory Syndrome in Children Treatment

This is a retrospective chart review of 20 patients treated with a consensus-driven treatment algorithm in multisystem inflammatory syndrome in children patients across a wide clinical spectrum. Their treatments and clinical status are described as well as their favorable return to functional baseline by 30 days post presentation.

CD45 tyrosine phosphatase controls common gamma-chain cytokine-mediated STAT and extracellular signal-related kinase phosphorylation in activated human lymphoblasts: inhibition of proliferation without induction of apoptosis

The objective of this study was to test whether CD45 signals can influence signaling processes in activated human lymphoblasts. To this end, we generated lymphoblasts which proliferate in response to common gamma-chain cytokines, but readily undergo apoptosis after cytokine withdrawal. In experiments with the CD45R0 mAb UCHL-1, but not control CD45 mAbs, we found significant inhibition of proliferation. Interestingly, the pan-CD45 mAb GAP8.3, which is most effective in inhibition of OKT-3-mediated proliferation in quiescent lymphocytes, was ineffective in lymphoblasts. Addition of CD3 mAb OKT-3 had no influence on IL-2-mediated proliferation (with or without UCHL-1). In contrast, after addition of OKT-3 to IL-4- and IL-7-stimulated proliferation assays, UCHL-1 signals could not significantly alter cellular proliferation. We did not find induction of apoptosis following CD45R0 signaling. In Western blots using mAbs detecting phosphorylated STAT-3, STAT-5, STAT-6, or extracellular signal-related kinase 1/2, we found that CD45R0 signaling could effectively diminish phosphorylation of these intracellular signaling components. Using RT-PCR, we found that CD45R0 signaling inhibited IL-2 mRNA production without major influence on IL-13, IL-5, or IFN-gamma mRNA levels. Costimulation with OKT-3 and IL-2 optimally induced secretion of IFN-gamma, TNF-alpha, and IL-5, which was not decreased by CD45 signals. In conclusion, we illustrate that CD45R0 signals control early cytokine receptor-associated signaling processes and mRNA and DNA synthesis in activated human lymphoblasts. Furthermore, we show the existence of CD45 epitopes (GAP8.3), which are active and critical for signaling in quiescent lymphocytes, but are nonfunctional in activated human lymphoblasts.

[The sexual activity of Culicoides nubeculosus (Mg.) (Diptera, Ceratopogonidae) (author's transl)]

The sexual activity of C. nubeculosus has been studied in relation to the age of males and females. The criteria chosen were stoutness of spermatheca and frequency of mating, respectively. A unit N. M. H. (number of matings/male/hour) has been determined. Sexual activity reaches its maximum on 2nd day of imaginal life and is then slowly decreasing. This maximum activity on 2nd day rapidly decreases in the hours following blood meal, down to a rate which then remains nearly constant.