POS1453 OVERLAPPING FEATURES OF RELAPSING POLYCHONDRITIS AND SWEET’S SYNDROME: COULD THIS BE VEXAS (VACUOLES, UBIQUITIN A1E MUTATION, X-LINKED, AUTOINFLAMMATORY, SOMATIC) SYNDROME?

Background:

An 83-year-old male presented to the infectious diseases team with intermittent fevers associated with tension headaches, malaise and fatigue for two years, with recent worsening. He had noted a progressive decline in his mobility over the past year following replacement of his right knee for osteoarthritis. His past medical history included atopic eczema, malaria and bilateral cataract extractions.

On examination, he had a widespread non-scaly annular urticated rash. He had persistently raised inflammatory markers (CRP 40mg/L, ESR 82mm/hour), normocytic anaemia (Hb 102 g/L, MCV 101.9 fL), lymphopenia (0.70 x10^9/L), fluctuating eosinophilia (0.88-1.25 x10^9/L) and a mildly elevated lactate dehydrogenase (243IU/L). A thorough work up for pyrexia of unknown origin showed no evidence of infection/ vasculitis/ immune pathology. The only positive finding was prior exposure to schistosomiasis, treated with a single dose of praziquantel. An echocardiogram and serial PET-CT scans were normal. Given the deterioration in mobility since the right knee replacement, an MRI knee was performed, and cobalt/ chromium levels to look for allergic responses to the prosthesis, but these tests did not reveal any findings of significance.

An initial haematology work-up did not identify an abnormality of concern (screening for a myeloproliferative neoplasm including BCR-ABL studies were negative and mast cell tryptase was not elevated). Due to a worsening skin rash, he was reviewed by dermatology where a skin biopsy showed features of superficial neutrophilic dermatosis which can be observed with Sweet’s syndrome. However, it was felt that this was an unlikely explanation for the persistent systemic symptoms. He proceeded to a bone marrow biopsy which showed reactive features including vacuolation of myeloid precursors with normal cytogenics.

During follow up appointments, the patient described new recurrent violaceous patches with episodes of inflammation of the pinna of the ear, suggesting a diagnosis of relapsing polychondritis and so the patient was started on high dose prednisolone (80mg per day [1mg per kg]) and referred for rheumatological assessment. He had an excellent response to prednisolone (fever, ear swelling and rash subsided). The overlapping features of relapsing polychondritis and Sweet’s syndrome in an elderly man suggested a diagnosis of VEXAS (vacuoles, E1 enzyme, X-linked, autoinflammatory and somatic) syndrome. The prednisolone dose was rapidly reduced to 10mg per day and the patient was commenced on methotrexate, as a steroid-sparing agent. Further blood tests have been sent for genetic analysis for VEXAS syndrome but results are pending.

Objectives:

N/A

Methods:

N/A

Results:

N/A

Conclusion:

VEXAS syndrome is a newly identified genetically defined syndrome, described by Beck et al in October 2020 consisting of somatic mutations in the UBA1 gene, affecting bone marrow stem cells. In a study of 25 patients with this mutation, diagnostic/ classification criteria for relapsing polychondritis (n=15), Sweet’s syndrome (n=8), polyarteritis nodosa (n=3) or giant cell arteritis (n=1) were met and patients often had severe refractory disease with overlapping systemic inflammatory and haematologic features. Features of VEXAS include the presence of vacuoles in myeloid cells, somatic mutations in the UBA1 (ubiquitin-activating enzyme) gene, X-linkage (therefore only occurring in males), in older people with autoinflammatory syndromes. Although VEXAS syndrome is a relatively rare condition, it was a relevant consideration in this case.

References:

[1]Beck et al. Somatic Mutations in UBA1 and Severe Adult-Onset Autoinflammatory Disease. N Engl J Med 2020; 383:2628-2638. DOI: 10.1056/NEJMoa2026834

Disclosure of Interests:

None declared

Septicaemia models using Streptococcus pneumoniae and Listeria monocytogenes: understanding the role of complement properdin

Streptococcus pneumoniae and Listeria monocytogenes, pathogens which can cause severe infectious disease in human, were used to infect properdin-deficient and wildtype mice. The aim was to deduce a role for properdin, positive regulator of the alternative pathway of complement activation, by comparing and contrasting the immune response of the two genotypes in vivo. We show that properdin-deficient and wildtype mice mounted antipneumococcal serotype-specific IgM antibodies, which were protective. Properdin-deficient mice, however, had increased survival in the model of streptococcal pneumonia and sepsis. Low activity of the classical pathway of complement and modulation of FcγR2b expression appear to be pathogenically involved. In listeriosis, however, properdin-deficient mice had reduced survival and a dendritic cell population that was impaired in maturation and activity. In vitro analyses of splenocytes and bone marrow-derived myeloid cells support the view that the opposing outcomes of properdin-deficient and wildtype mice in these two infection models is likely to be due to a skewing of macrophage activity to an M2 phenotype in the properdin-deficient mice. The phenotypes observed thus appear to reflect the extent to which M2- or M1-polarised macrophages are involved in the immune responses to S. pneumoniae and L. monocytogenes. We conclude that properdin controls the strength of immune responses by affecting humoral as well as cellular phenotypes during acute bacterial infection and ensuing inflammation.

The use of dried cerebrospinal fluid filter paper spots as a substrate for PCR diagnosis of the aetiology of bacterial meningitis in the Lao PDR

We investigated whether dried cerebrospinal fluid (CSF) conserved on filter paper can be used as a substrate for accurate PCR diagnosis of important causes of bacterial meningitis in the Lao PDR. Using mock CSF, we investigated and optimized filter paper varieties, paper punch sizes, elution volumes and quantities of DNA template to achieve sensitive and reliable detection of bacterial DNA from filter paper specimens. FTA Elute Micro Card™ (Whatman, Maidstone, UK) was the most sensitive, consistent and practical variety of filter paper. Following optimization, the lower limit of detection for Streptococcus pneumoniae from dried mock CSF spots was 14 genomic equivalents (GE)/μL (interquartile range 5.5 GE/μL) or 230 (IQR 65) colony forming units/mL. A prospective clinical evaluation for S. pneumoniae, S. suis and Neisseria meningitidis was performed. Culture and PCR performed on fresh liquid CSF from patients admitted with a clinical diagnosis of meningitis (n = 73) were compared with results derived from dried CSF spots. Four of five fresh PCR-positive CSF samples also tested PCR positive from dried CSF spots, with one patient under the limit of detection. In a retrospective study of S. pneumoniae samples (n = 20), the median (IQR; range) CSF S. pneumoniae bacterial load was 1.1 × 10(4) GE/μL (1.2 × 10(5) ; 1 to 6.1 × 10(6) DNA GE/μL). Utilizing the optimized methodology, we estimate an extrapolated sensitivity of 90%, based on the range of CSF genome counts found in Laos. Dried CSF filter paper spots could potentially help us to better understand the epidemiology of bacterial meningitis in resource-poor settings and guide empirical treatments and vaccination policies.

Clinical audit of linezolid use in a large teaching hospital

OBJECTIVES

Linezolid, the first available agent in the new class of oxazolidinone antibiotics, represents a significant advance in the management options available for combating methicillin-resistant Staphylococcus aureus (MRSA) infections. In the UK it was launched for clinical use in 2001. The aim of this study was to audit the clinical use of linezolid and compliance with the guidelines of the hospital antibiotic committee.

METHODS

Our hospital antibiotic committee agreed clinical indications for linezolid use. We undertook an audit of compliance with these recommendations and also reviewed its use in terms of the source of infection, microbiology, duration of therapy, side-effects and choice of previous treatment.

RESULTS

Seventy-seven inpatients prescribed linezolid in Ninewells Hospital in the 3 years between March 2001 and September 2003 were audited. Overall compliance with our local recommendations appears to be very good. The main justification for using linezolid is the presence of existing or worsening renal dysfunction or poor venous access (34%) or lack of tolerance or clinical failure following glycopeptide monotherapy or combination therapy (32%). Skin and soft tissue infections (26%) were the most frequently diagnosed infections, although an increasing number of patients appear to receive linezolid for the treatment of lower respiratory tract infections, primarily in the ICU for nosocomial or ventilator-associated pneumonia. MRSA organisms were the most common cause of microbiologically proven treated infections [n = 43 (56%)]. Disappointingly, only 34 out of 77 patients had case record documentation of prior approval by an infection specialist.

CONCLUSIONS

The use of linezolid in our hospital appears to follow local guidelines, but the quality of information recorded in the notes could be optimized. Consequently, a linezolid mandatory order form to be completed by the attending prescribing clinician has been introduced, and will be subject to future evaluation. We recommend such specific antibiotic utilization reviews or audits of new agents introduced into clinical infection practice.

MEG predicts epileptic zone in lesional extrahippocampal epilepsy: 12 pediatric surgery cases

PURPOSE

To discover whether the spatial distribution of spike sources determined by magnetoencephalography (MEG) provides reliable information for planning surgery and predicting outcomes in pediatric patients with lesional extrahippocampal epilepsy.

METHODS

We retrospectively studied 12 children with extrahippocampal epilepsy secondary to cortical dysplasia (CD), tumor, or porencephalic cyst. We compared interictal MEG spike source locations and somatosensory evoked fields derived from equivalent-current dipole modeling with intraoperative or extraoperative electrocorticography (ECoG).

RESULTS

MEG spike sources were found in proximity to the lesion in all patients and extended from lesions in five patients with CD. Marginal spike sources were noted in three patients with tumors, one patient with a cyst, and one with CD, and extramarginal sources in three patients with tumors. Three patients with tumors underwent lesionectomy only; two had further cortical excisions. One patient with CD underwent lesionectomy only, three had lesionectomy and cortical excisions, and two had lesionectomy and multiple subpial transection. Asymmetric MEG spike sources correlated with ECoG findings in all patients. Residual epileptiform discharges on postexcisional ECoG corresponded to spike sources in three patients with tumors and one patient with a cyst. Eleven patients have been seizure free for 1-6 years (mean, 4 years). One patient had residual seizures after incomplete excision of right temporal CD.

CONCLUSIONS

MEG delineated asymmetric epileptogenicity surrounding lesions and the eloquent cortex. Complete tumor resection produced favorable outcomes despite residual postexcisional ECoG spikes and extramarginal MEG spike sources. CD characterized by clusters of MEG spike sources within and extending from lesions seen on magnetic resonance imaging (MRI) should be removed to prevent seizures.

Magnetoencephalographic localization in pediatric epilepsy surgery: comparison with invasive intracranial electroencephalography

The object of this study was to determine the concordance of the anatomical location of interictal magnetoencephalographic (MEG) spike foci with the location of ictal onset zones identified by invasive ictal intracranial electroencephalographic recordings in children undergoing evaluation for epilepsy surgery. MEG was performed in 11 children with intractable, nonlesional, extratemporal, localization-related epilepsy. Subsequently, chronic invasive intracranial electroencephalographic monitoring was performed by using subdural electrodes to localize the ictal onset zone and eloquent cortex. Based on the invasive monitoring data, all children had excision of, or multiple subpial transections through, ictal onset cortex and surrounding irritative zones. In 10 of 11 patients, the anatomical location of the epileptiform discharges as determined by MEG corresponded to the ictal onset zone established by ictal intracranial recordings. In all children, the anatomical location of the somatosensory hand area, determined by functional mapping through the subdural electrode array, was the same as that delineated by MEG. Nine of 11 patients became either seizure-free or had a greater than 90% reduction in seizures after surgery, with a mean follow-up of 24 months. MEG is a powerful and accurate tool in the presurgical evaluation of children with refractory nonlesional extratemporal epilepsy.

Confirmation of two magnetoencephalographic epileptic foci by invasive monitoring from subdural electrodes in an adolescent with right frontocentral epilepsy

PURPOSE

To report our evaluation of interictal two epileptic spike fields on magnetoencephalography (MEG) by using invasive intracranial monitoring in a patient without lesion on magnetic resonance imaging (MRI).

METHODS

A 15-year-old left-handed boy with a 9-year history of refractory simple partial seizures, secondarily generalized, and a normal MRI, was studied with MEG to define magnetic spike sources, followed by invasive intracranial monitoring with subdural electrodes to delineate the epileptogenic zone and eloquent function pursuant to focal cortical excision.

RESULTS

MEG demonstrated two spike foci on the right middle frontal and inferior rolandic areas adjacent to the sensory area. Ictal recordings during prolonged invasive monitoring from subdural electrodes revealed two epileptogenic zones in the same locations as those defined by MEG. Focal cortical excision was performed of each epileptogenic zone. The patient has been seizure free for 24 months without neurologic deficit.

CONCLUSIONS

Magnetic source imaging is a valuable adjunct in the planning of subdural grid placement in epilepsy surgery, particularly in patients in whom conventional imaging fails to reveal a lesion.

Association between duration of neonatal hospital stay and readmission rate

OBJECTIVE

A recent rapid decrease in the duration of neonatal hospital stay in Ontario, Canada, enabled us to study the association between healthy infants' age at neonatal hospital discharge and subsequent readmission rates.

DESIGN

(1) Population-based and (2) single hospital-based retrospective studies.

SETTING AND STUDY POPULATION

(1) A total of 920,554 healthy infants with a birth weight of 2500 gm or more, born in Ontario from 1987 to 1994. (2) Infants with a birth weight of 2500 gm or more, born during the same period, and readmitted before 15 days from home to the Hospital for Sick Children for jaundice or dehydration.

MEASUREMENT

Duration of neonatal stay in the hospital and readmission rates were measured, and diagnostic codes were analyzed. Severity of illness was evaluated in infants readmitted to our hospital.

RESULTS

In Ontario the mean length of stay decreased from 4.5 days to 2.7 days (p = 0.000), and the readmission rate during the first 2 weeks of life increased from 12.9 to 20.7 per 1000 (p = 0.000). Increased rates of readmission were most marked for jaundice and dehydration. The infants readmitted to our hospital had evidence of increased severity of illness as indicated by higher serum bilirubin and sodium concentrations. Two deaths occurred in infants with hypernatremic dehydration, one in 1992-1993 and another in 1993-1994.

CONCLUSIONS

In Ontario, shorter neonatal hospital stay was associated with increased readmission rates for conditions that may not give rise to symptoms or signs on days 1 to 3 of life. In our hospital the severity of jaundice and dehydration in readmitted infants increased. The severity-of-illness data raise the question of whether shorter neonatal hospital stay of apparently healthy infants is always safe. Decisions to discharge infants should be based on rigorous evaluation of individual infants.

Psychosocial functioning in adolescents with complex partial seizures

This pilot study examined psychosocial functioning in adolescents (age 12.5-18.5 years) with complex partial seizures. Twenty-five subjects were divided into three groups: Group I (N = 11), medically treated with uncontrolled seizures; Group II (N = 6), medically managed with controlled seizures; and Group III (N = 8), epilepsy refractory to medical management with seizure control following surgery. Psychosocial functioning was measured using the "Adolescent Psychosocial Inventory" of Batzel and Dodrill. Findings revealed significant differences (F 4.80. p less than 0.02) in psychosocial functioning between the three groups. Group I showed the poorest overall adjustment; Group II, the best adjustment; Group III was better adjusted than Group I, but less than Group II. Significant difficulties were evident in the areas of school, interpersonal, emotional, seizure adjustment and overall psychosocial functioning in Group III. No problems were evident in Group II. School, emotional and overall adjustment were moderately problematic in Group III. Analysis of biological and demographic data revealed a significant association between increased numbers of medications and poorer psychosocial functioning (r = 58, p less than 0.02). The study results provide direction for clinic and community nurse specialists to set priorities with regard to assessment and supportive interventions.