Insights into SARS-CoV-2 Persistence and Its Relevance.

Severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2), the causative agent of coronavirus disease 2019 (COVID-19), continues to wreak havoc, threatening the public health services and imposing economic collapse worldwide. Tailoring public health responses to the SARS-CoV-2 pandemic depends on understanding the mechanism of viral replication, disease pathogenesis, accurately identifying acute infections, and mapping the spreading risk of hotspots across the globe. However, effective identification and isolation of persons with asymptomatic and mild SARS-CoV-2 infections remain the major obstacles to efforts in controlling the SARS-CoV-2 spread and hence the pandemic. Understanding the mechanism of persistent viral shedding, reinfection, and the post-acute sequalae of SARS-CoV-2 infection (PASC) is crucial in our efforts to combat the pandemic and provide better care and rehabilitation to survivors. Here, we present a living literature review (January 2020 through 15 March 2021) on SARS-CoV-2 viral persistence, reinfection, and PASC. We also highlight potential areas of research to uncover putative links between viral persistence, intra-host evolution, host immune status, and protective immunity to guide and direct future basic science and clinical research priorities.

Rasburicase induced severe hemolysis and methemoglobinemia in a Caucasian patient complicated by acute renal failure and ARDS.

Rasburicase is a recombinant urate-oxidase enzyme and is a very important medication for tumor lysis syndrome. Methemoglobinemia and hemolysis are known side effects of rasburicase that result from oxidative stress caused by hydrogen peroxide, a byproduct generated during the breakdown of uric acid to allantoin. Patients with G6PD deficiency have a decreased tolerance to oxidative stress and are therefore at a greater risk of hemolysis and methemoglobinemia with rasburicase. Our patient is a 56-year-old Caucasian male with a recent diagnosis of grade 2-3a non-Hodgkin's lymphoma who presented to our emergency department with shortness of breath and dark discoloration of urine. Patient was discharged 36 hours ago from our hospital after he was given a first course of R-CHOP regimen and a dose of rasburicase. On further evaluation, patient was found to have severe anemia with hemolytic picture, hyperkalemia and acute kidney injury. He also had a discrepancy of the transcutaneous saturation (75%) and the saturation in an arterial blood gas value (99%). His methemoglobin level was found to be 11.9%. We were aware that methylene blue is a contraindication in patients with G6PD deficiency but considering patient being Caucasian and low risk for it and his deteriorating respiratory condition, it was decided to offer the treatment and patient received 1 dose of methylene blue which failed to improve his methemoglobinemia. He was also given vitamin C and 8 units of packed red blood cell throughout his stay in the hospital. Patient's hospital course was complicated by ARDS needed to be on mechanical ventilation support for 4 days and acute renal failure secondary to pigment nephropathy and acute tubular necrosis which required a hemodialysis support. Even if rasburicase induced methemoglobinemia and hemolysis are not very common complications, clinicians who prescribe and follow patients should detect this serious complication early and manage it accordingly. Our case can be used as a reminder that patients should be followed closely and given the right instructions on discharge to treat these complications which are associated with severe consequences. It is also vital to assume a diagnosis of G6PD deficiency until proven otherwise in a patient who presents with rasburicase induced hemolysis and avoid administration of methylene blue even if the patient is from a low risk ethnicity for G6PD as in our patient.

Pulmonary vein thrombosis secondary to tuberculosis in a non-HIV infected patient.

Our patient is a 67-year-old male with a past medical history significant for hypertension and hyperlipidemia came to a hospital with hemoptysis. He was also having cough and shortness of breath for the last 1 month. He said that his hemoptysis was about 1 cup per day mixed with yellowish sputum. He noticed around 20 pounds of weight loss in the last 1 month. He also complained of night sweats but had no fever. He had no history of travel outside the USA. He has never been incarcerated before, but he endorsed that his son has been to Jail before and he visited him twice a year in patient's home. But he also said that his son has never been diagnosed with TB. He smoked 1.5 packs per day for the last 50 years and quit smoking 2 months ago. His medication include hydrochlorothiazide, lisinopril, gabapentin, aspirin and trazodone. On examination, vital signs were within the normal range except a hearty rate of 106 beats/minute. He had slightly pale conjunctiva, non-icteric sclera and had wet tongue and buccal mucosa. There was decreased air entry with crepitations in the right side of the posterior chest but no wheezes or rales. No peripheral lymphadenopathy, no peripheral edema or sign of fluid collection in the abdomen. Chest x ray showed multiple cavitary lesion in the right upper lobe area. CT scan of the chest with PE protocol showed pulmonary venous partial thrombosis in the right upper lobe. Multiple cavitary lesions with hilar and mediastinal lymphadenopathy. There are also smaller nodular lesions in the left chest too. Small right pleural effusion with multiple calcified granulomata in the left upper lobe. QuantiFERON gold test was found to be positive. Sputum AFB smear was found to be strongly positive and it is sensitive to rifampin. Echocardiography showed no valvular lesions with preserved ejection fraction (>65%) and normal right ventricular size and normal right ventricular systolic pressure. Liver enzymes and renal function tests were found within the normal limit. HIV test was negative. Patient was started with intensive phase anti-tuberculosis treatment with rifampin, isoniazid, ethambutol, pyrazinamide with vitamin B6. He was also started with anticoagulation with heparin and warfarin considering the tuberculosis being the cause of the pulmonary vein thrombosis. Patient was also given supportive treatment and he made a gradual improvement and was discharged with anti-tuberculosis treatment and warfarin. Patient needed to be placed on a higher dose of warfarin as it was difficult to keep him therapeutic with lower doses. He was also advised to follow with infectious disease and anticoagulation clinic. Patient was found to have a significant increase in liver enzymes and bilirubin on follow up and the anti-TB medications were stopped to be restarted one by one with a follow up of his liver enzymes and liver function tests. He was also continued with warfarin.

Ammonia vs. Lactic Acid in Predicting Positivity of Microbial Culture in Sepsis: The ALPS Pilot Study.

OBJECTIVE: The use of serum ammonia as a novel marker for sepsis compared to lactic acid levels in intensive care unit (ICU) patients. DESIGN AND INTERVENTIONS: Single arm, prospective clinical trial to collect arterial blood samples from patients with sepsis. Serial ammonia and lactic acid levels were sent every six hours for a total of three days. MEASUREMENTS AND RESULTS: Compare mean levels of ammonia and lactic acid in terms of diagnosing sepsis and patient outcome, including length of stay and mortality. A total of 30 patients were enrolled in the pilot study. On admission, mean ammonia level was 35.7 µmol/L and lactic acid was 3.06 mmole/L. Ammonia levels checked at the end of day 2 (ammonia 2-4) and the beginning of day 3 (ammonia 3-1) were higher in patients who had a microbial culture-proven sepsis (p-values 0.029 and 0.002, respectively) compared to those without culture-positive sepsis. Ammonia levels did predict a longer hospital stay; ammonia level of more than 40 µmol/L had a mean hospital stay of 17.6 days vs. patients with normal levels who had a mean hospital stay of 9.62 days (p-value 0.0082). CONCLUSION: Elevated ammonia level can be a novel biomarker for sepsis, comparable to conventional markers. Ammonia levels have a prognostic utility as elevated levels were associated with longer hospital stay.

Hypoxic respiratory failure due to hyperammonemic encephalopathy induced by concurrent use of valproic acid and topiramate, a case report and review of the literature.

Valproic acid (VPA) is widely used for the treatment of epilepsy, migraine, and a variety of psychiatric symptoms, including bipolar disorder, borderline personality disorder, and alcohol withdrawal. Valproate is associated with severe idiosyncratic adverse effects, the most notable being valproate-induced hyperammonemic encephalopathy (VHE). Topiramate is also a broad-spectrum anticonvulsant that is also extensively used for migraine prophylaxis, as a mood stabilizer, and for alcohol dependency. There is increased occurrence of VHE when valproate is used with other medications like phenytoin, phenobarbital, and topiramate. Our case report is on a young patient who was on valproic acid and topiramate and developed metabolic encephalopathy with hypoxic respiratory failure. We reviewed the causes and management of the hyperammonemic encephalopathy. We believe that clinicians should be aware of possible hyperammonemic encephalopathy in any patient who is taking valproic acid and presenting with impaired consciousness and cognitive decline. We also underline the importance of early recognition and high index of suspicion of encephalopathy related to hyperammonemia.

Two patients with daptomycin induced eosinophilic pneumonia with different presentations and treatment.

We present two cases of daptomycin-induced eosinophilic pneumonia with characteristic chest x ray, CT scan and bronchoalveolar lavage (BAL) findings. It is not a commonly seen complication of Daptomycin but when it happens, it could cause a diagnostic and treatment dilemma. Patients could present acutely with hypoxic respiratory failure or a less dramatic chronic presentation is also possible. Our two patients presented with acute hypoxic respiratory failure and presentation resembles that of an infectious etiology. Diagnosis is confirmed by bronchoscopy with BAL in one of them and the other was treated empirically as the clinical and radiologic presentation was typical. Treatment includes removal of the offending agent, daptomycin. Corticosteroids are used if symptoms are severe and can result in rapid clinical improvement. There is no agreed upon dose and duration of steroids and we suggest a long taper of steroids for patients who present with severe symptoms and a short course steroid for patients with milder symptoms.