458. Molecular SARS-CoV-2 Testing During the COVID-19 Outbreak: Experiences of a Hospital in Southeast Michigan, USA

Background

The novel Coronavirus SARS CoV-2 (COVID-19) outbreak was complicated by the lack of diagnostic testing kits. In early March 2020, leadership at Beaumont Hospital, Royal Oak Michigan (Beaumont) identified the need to develop high capacity testing modalities with appropriate sensitivity and specificity and rapid turnaround time. We describe the molecular diagnostic testing experience since initial rollout on March 16, 2020 at Beaumont, and results of repeat testing during the peak of the COVID-19 pandemic in MI.

Methods

Beaumont is an 1100 bed hospital in Southeast MI. In March, testing was initially performed with the EUA Luminex NxTAG CoV Extended Panel until March 28, 2020 when testing was converted to the EUA Cepheid Xpert Xpress SARS-CoV-2 for quicker turnaround times. Each assay was validated with a combination of patient samples and contrived specimens.

Results

During the initial week of testing there was > 20 % specimen positivity. As the prevalence grew the positivity rate reached 68% by the end of March (Figure 1). Many state and hospital initiatives were implemented during the outbreak, including social distancing and screening of asymptomatic patients to increase case-finding and prevent transmission. We also adopted a process for clinical review of symptomatic patients who initially tested negative for SARS-CoV-2 by a group of infectious disease physicians (Figure 2). This process was expanded to include other trained clinicians who were redeployed from other departments in the hospital. Repeat testing was performed to allow consideration of discontinuation of isolation precautions. During the surge of community cases from March 16 to April 30, 2020, we identified patients with negative PCR tests who subsequently had repeat testing based on clinical evaluation, with 7.1% (39/551) returning positive for SARS- CoV2. Of the patients who expired due to COVID-19 during this period, 4.3% (9/206) initially tested negative before ultimately testing positive.

Figure 1 BH RO testing Epicurve

Figure 2: Screening tool for repeat COVID19 testing and precautions

Conclusion

Many state and hospital initiatives helped us flatten the curve for COVID-19. Our hospital testing experience indicate that repeat testing may be warranted for those patients with clinical features suggestive of COVID-19. We will further analyze these cases and clinical features that prompted repeat testing.

Disclosures

All Authors: No reported disclosures

1653. Strong Partnership and Effective Communication Between a Tertiary Hospital and a County Health Department Were Critical in Controlling a 2019 Measles Outbreak in Southeast Michigan (SEM)

Background

Measles, declared eliminated in the US 2000, is a reemerging vaccine-preventable airborne disease. The 2019 case count (704 as of April 30, 2019) has surpassed the number of 2014 cases (667), the highest since 1994. Many healthcare personnel (HCP) have not seen a case of measles, and this lack of clinical experience may contribute to missed or delayed diagnoses leading to its spread. We describe the processes and measures implemented at Beaumont Hospital, Royal Oak (B-RO) Michigan in collaboration with the Oakland County Health Department (OCHD) to prevent secondary spread during an outbreak.

Methods

Soon after the initial report of the index case in Oakland County in March, the B-RO epidemiology team connected with OCHD. As both exposed and suspected cases were expected to seek care at B-RO, a one-page informational document was sent to B-RO providers. This document detailed isolation precautions and testing methods, post-exposure prophylaxis (PEP), and contact information. During subsequent days, as measles cases increased, frequent calls between B-RO and OCHD addressed numerous issues, including: media notifications, contact of exposed persons, vaccine and immunoglobulin supply for PEP, safe referral of cases to the EC, and the process of measles specimen submission for testing. As needed, these communications occurred after business hours and during weekends. Serologic testing to confirm measles immunity was ramped up.

Results

As of April 30, 41 cases have been confirmed in MI associated with the index case. OCHD facilitated the exposure control for 40 patients, of which 6 came to B-RO during their infectious period (Figure 1). To date, there have been no secondary cases developing in B-RO patients, HCPs or visitors, which may be related to successful engineering controls, appropriate protective equipment, mandatory measles immunity confirmation as condition of Beaumont employment since the late 1980s, institution of furlough procedures, PEP for hospitalized patients, and widespread communications with patients, visitors and HCPs (Figure 2).

Conclusion

During an outbreak, close healthcare facility and local health department collaboration is essential in rapidly limiting an airborne disease outbreak.

Disclosures

All authors: No reported disclosures.

Acoustic neuromas: results of current surgical management

OBJECTIVE

In this article, we review the surgical outcomes of 179 patients with acoustic neuromas.

METHODS

Most of the tumors (84%) were operated on using a retrosigmoid, transmeatal approach. A transpetrosal, retrosigmoid approach was used in 10% of the patients, most of whom had large tumors. The translabyrinthine (4%) and transmastoid, transpetrosal, partial labyrinthectomy approaches (2%) were used selectively. The operative approaches are discussed. Tumors were categorized according to their cerebellopontine angle dimensions as small (< 2 cm), medium (2.0-3.9 cm), and large (> or = 4 cm).

RESULTS

House-Brackmann evaluation of postoperative facial nerve function revealed excellent results (Grade I or II) in 96% of small tumors, 74% of medium tumors, and 38% of large tumors. A fair postoperative function (Grade III or IV) was achieved in 4% of small tumors, 26% of medium tumors, and 58% of large tumors. Functional hearing preservation, defined as Gardner-Robertson Class I or II, was achieved in 48% of small tumors and 25% of medium tumors. Hearing was not preserved in any of the three patients with large tumors in whom hearing preservation was attempted. Treatment complications consisted mainly of cerebrospinal fluid leakage (15% of the patients). The majority of the patients who experienced cerebrospinal fluid leakage were treated successfully with lumbar spinal drainage; only four patients (2% of the total group) required subsequent surgery for correction of cerebrospinal fluid leakage. There were two deaths (1%) in this series. One death occurred as the result of myocardial infarction and the other as the result of severe obstructive lung disease. One patient sustained disability because of cerebellar and brain stem injury. Complete tumor resection was accomplished in 99% of the patients, and there was no evidence of recurrence in this group. Only 1 of the 179 patients underwent incomplete tumor resection; he required subsequent surgery for symptomatic tumor regrowth. Our patient follow-up had a mean duration of 70 months and a median of 65 months (range, 3-171 mo).

CONCLUSION

Our results are similar to those of other large microsurgical series of acoustic neuromas. Unless a patient has major medical problems, microsurgery by an experienced team of surgeons is preferred over radiosurgery.

Late course of preserved hearing and tinnitus after acoustic neurilemoma surgery

The late course of preserved hearing and tinnitus following retrosigmoid transmeatal surgery for acoustic neurilemoma is reported. Over a period of 5 years, useful hearing was preserved in 15 patients after preservation was attempted in 42 patients. In five patients the hearing was better than the preoperative level; in three it was worse. Three patients developed delayed worsening and fluctuations of hearing in the surgically treated ear during a median follow-up period of 2 1/2 years. While the exact reason for such worsening was not clear in two patients, in one patient it appeared that the muscle graft placed in the internal auditory canal after tumor resection resulted in fibrosis and compromise of the cochlear nerve. The causes of delayed worsening of hearing in the absence of tumor recurrence are analyzed, and possible treatment and methods of prevention of worsening are suggested. In six patients, tinnitus persisted after surgery in the ear with successful preservation of hearing, but hearing was not worsened and the tinnitus was not bothersome to the patient. In one patient with preoperative tinnitus, hearing was not preserved and tinnitus persisted sufficiently to necessitate reexploration and cochlear nerve section.

Moxalactam therapy. Its use in chronic suppurative otitis media and malignant external otitis

Moxalactam disodium is a new broad-spectrum antibiotic structurally related to the cephalosporins. Eleven patients with chronic suppurative otitis media with mastoiditis and four patients with malignant external otitis were treated with moxalactam. Pseudomonas aeruginosa was isolated from external ear or mastoid in all patients. Twelve of 15 patients had undergone prior surgical procedures and 11 of 15 had failed recent antibiotic therapy. Three patients with malignant external otitis did not respond to parenteral carboxypenicillin and aminoglycoside therapy. Success rate for chronic suppurative otitis media was 73% as judged by eradication of P aeruginosa and resolution of symptoms 30 days after moxalactam therapy. Two patients with malignant external otitis were cured, and two were unevaluable since they may have died of noninfectious causes. Moxalactam disodium, at a dosage of 9 g/day, may be useful for serious Pseudomonas ear infections, including those refractory to other antibiotic therapy.