Authors: Li Xuejie1 Wang Ming2 Dai Jing3Wang Wenjun3Yang Yanning3Jin Wei3
1The First Affiliated College of Wuhan University, Wuhan 430060, China；2Department of Clinical Laboratory, Renmin Hospital of Wuhan University, Wuhan 430060, China；3Eye Center, Renmin Hospital of Wuhan University, Wuhan 430060, China
Corresponding author: Jin Wei, Email:firstname.lastname@example.org
[Abstract] As the frontline health care workers at the center of the novel coronavirus disease (COVID-19) outbreak, we have encountered many asymptomatic COVID-19 patients or patients with mild symptoms since December 2019. A number of COVID-19 cases with conjunctivitis or conjunctivitis as the first symptom have been observed in our clinical work. This paper reports the diagnosis and treatment of one COVID-19 patient with conjunctivitis as the first symptom and one COVID-19 patient with conjunctivitis. In case one, conjunctivitis occurred the third day after the patient came in close contact with a determined COVID-19 patient; the patient visited an eye doctor, the conjunctivitis was treated for one week, after which symptoms of COVID-19 appeared. Her nasopharynx swab for 2019-nCoV RNA detection was positive, but her conjunctival sac swab was negative. Case two had a positive epidemiological history and simultaneous onset of COVID-19 and conjunctivitis. Her nasopharynx and conjunctival sac swabs for 2019-nCoV RNA detection both had a positive result, and other lab results supported the diagnosis of COVID-19, but she had a normal CT findings of the chest. The ocular symptoms disappeared after topical administration of anti-viral eyedrops for one week.
[Key words] Novel coronavirus disease; Conjunctivitis; Novel coronavirus; Infectious disease; Transmisson; Case report
Novel coronavirus disease (COVID-19) broke out in Wuhan, China in December 2019 and quickly spread across worldwide. 2019-nCoV belongs to coronavirus family. It is an enveloped RNA virus with spherical particles and certain pleomorphism. Current research shows it has more than 85% homology with SARS-CoV (bat-SL-CoVZC45) that causes severe acute respiratory syndrome . At present, the diagnosis of COVID-19 mainly depend on clinical features, CT/X-ray imaging and the real-time PCR test for nucleic acid in respiratory samples (nasopharyngeal swab) . However, in the actual clinical work, many patients have extremely insidious onset. Some patients start with minor clinical signs or even no clinical symptoms. In addition, we found that a small number of patients did not have typical respiratory symptoms such as fever and cough, but only took ophthalmic symptoms (such as conjunctivitis) as the first manifestation, which brought great difficulties and hidden dangers to early diagnosis and early isolation. The specific diagnosis and treatment of one patient with conjunctivitis as the first symptom and one patient with conjunctivitis in COVID-19 are reported .
Case1: A female anesthesiologist in a hospital of epidemic area with 49 years old performed endotracheal intubation during chest wall nerve block anesthesia for a breast cancer patient on January 18th, 2020. This patient who received intubation had not been diagnosed with COVID-19 at that time, so the anesthesiologist was only provided with routine protective way, including surgical masks, gloves, caps and surgical gowns, and did not wear protective goggles. On the morning of the third day after intubation, the left eye of the anesthesiologist presented with viscous secretion and mild hyperemia in the conjunctival sac, but no treatment was given. The same symptoms appeared in the right eye next day. Knowing that the patient who received intubation diagnosed with COVID-19 after operation, the anesthesiologist visited the Ophthalmic Center, Renmin Hospital of Wuhan University on January 22th, 2020, and conjunctival congestion and thin mucous secretions were seen in both eyes was found by slit lamp microscopy. The cornea and aqueous humor were clear, and lens were transparent. Fundus examination showed clear optic disc boundaries, normal color and normal retinal blood vessels. No hemorrhage, exudation or edema were found in macular area. Her chest CT image was normal and there were no symptoms of respiratory infection. The anesthesiologist was in good health, with no history of trauma, no family history or other systemic diseases. Initial diagnosis: binocular viral conjunctivitis. Ganciclovir eye drops and sodium hyaluronate eye drops were administered in both eyes for 4 times per day during home isolation. After one week, the eye symptoms basically disappeared.
On January 25th, the anesthesiologist began to experience sore throat and discomfort with cough and low fever up to 38.5°C. And she was confirmed COVID-19 with a positive result for 2019-nCoV nucleic acid of nasopharyngeal swab, but the 2019-nCoV nucleic acid from binocular conjunctival sac swab was negative. Her chest CT images showed typical COVID-19 findings. Thus, she was isolated and hospitalized for treatment. Auxiliary examination: 2020-01-29 serum amyloid (SAA) 28.86 mg/L. Detection of novel coronavirus antibodies: 2020-02-18 IgM: 10.23 AU/ml, IgG: 69.28 AU/ml; 2020-02-26 IgM: 12.77AU/ml, IgG: 90.42AU/ml; 2020-02-28 IgM: 10.01AU/ml, IgG: 87.01AU/ml. 2019-nCoV nucleic acid of nasopharyngeal swab showed a positive result on January 30th, February 15th, February 22nd and a negative result on February 26th. On February 28th, 2019-nCoV nucleic acid results showed that 2019-nCoV nucleocapsid protein gene was negative. 2019-nCoV open reading frame lab was positive, which tended to turn negative. Now the anesthesiologist is still being hospitalized.
Case 2: A female patient, 30 years old, is a nurse of hospital in epidemic area. Two days after working at the fever clinic, because of mild cough and eye itching, the nurse visited Rinmin Hospital of Wuhan University for medical examination on January 18th, 2020. The 2019-CoV nucleic acid test of nasopharyngeal swab and conjunctival sac swab were both positive, and was diagnosed as COVID-19 with conjunctivitis, but chest CT was not significantly abnormal at that time. On January 22nd, 2020, the patient developed sore throat, dizziness and headache, but no obvious fever, and she was admitted to being hospitalized for antiviral treatment. During hospitalization, the patient only had pharyngeal discomfort and mild conjunctival congestion with slight foreign body sensation in eyes. Conjunctival congestion and thin water secretion was seen in both eyes by slit lamp microscope. The cornea and aqueous humor were clear, and lens were transparent. Fundus examination showed nothing special. Initial diagnosis: binocular viral conjunctivitis. Local ganciclovir and sodium hyaluronate eye drops were given and the eye symptoms improved 5 days later. Auxiliary examination: 2020-02-04 No significant abnormalities in humoral immune function (Ig, C3, C4) and cellular immune function (CD3, 4, 8, 16, 19, 56); Novel coronavirus antibody detection (IgG + 1gM): 2020-02-19 IgM was negative, IgG: 152.08AU / mL. After 1 week of antiviral treatment, her clinical symptoms of COVID-19 disappeared completely. During the period of hospitalization, she has taken chest CT examinations many times and all the images were normal. 10 nasopharyngeal swab 2019-nCoV nucleic acid tests have been performed, and positive results were showed in 7 times, highly suspected in 1 time and negative in 2 times. Since the patient’s nasopharyngeal swab 2019-CoV returned positive, she is still being hospitalized for treatment.
Discussion: In the first case of COVID-19 patients, conjunctivitis was as the first symptom, the patient only had symptoms of conjunctivitis at early stage, with no symptoms of respiratory infection, and the chest CT image was normal. Tracing the history of exposure, it is most likely that the anesthesiologist was infected while intubating a COVID-19 patient. At that time, she did not wear goggles, and soon after endotracheal intubation she developed symptoms of binocular conjunctivitis. Therefore, we speculate that 2019-nCoV may enter the patient through the ocular conjunctival pathway. Another COVID-19 patient with symptoms of conjunctivitis in case 2 was positive for 2019-nCoV nucleic acid in the eye conjunctival sac swab, indicating that the virus could be transmitted through the eyes and replicated on the conjunctiva. In addition, Shen et al published an article in the Journal of Medical Virology, confirming that in the mixed samples of tears and conjunctiva secretions from 30 patients with non-severe COVID-19, one sample from a COVID-19 patient complicated with conjunctivitis was tested positive for 2019-nCoV nucleic acid. And they speculated that 2019-CoV could be transmitted through the conjunctiva.
For most respiratory viruses, after reaching the surface of the eye and causing ocular complications, they enter and infect the respiratory tract through the nasolacrimal duct system. Tears from the eye surface are transported through the lacrimal passage to the lower nasal meatus, draining the viruses from the eye tissue to the respiratory tract. In addition, the exchange of the immune system of the eye mucosa (consisting of conjunctiva, cornea, lacrimal gland and lacrimal drainage system) with nasolacrimal duct and nasal lymphoid tissue also promotes the transmission of the virus to the lower respiratory tract. Most respiratory viruses can cause infection as soon as they reach the surface of the eye, while infected individuals can expel a high load of virus when coughing and sneezing. And it is probable that the mucous membrane of the eyes of people around them happens to be exposed to high concentrations of infectious aerosols and pathogens. For medical staff, they are at a higher risk of occupational exposure when collecting respiratory samples, or operating endotracheal intubation, bronchoscopy and sputum suction that may produce aerosols or spray. During the SARS outbreak in 2003, a survey of hospitals in Toronto showed that direct eye exposure to body fluids or the absence of goggles significantly increased the risk of SARS-CoV transmission from infected patients to healthcare workers, indicating the possibility of SARS-CoV transmission through ocular after unprotected eye exposure to this respiratory pathogen. Through 5 case-control studies and 5 retrospective cohort studies, Zumbla et al  determined that procedures such as endotracheal intubation and tracheotomy increased the risk of SARS-CoV transmission to health care workers. They also pointed out that when caring for patients with suspected or confirmed MERS-CoV infection, preventive measures for contact procedures and eye protection should be added. And the hospital ventilation should be improved.
Recently, the research team at the University of Texas at Austin proved that the affinity of human angiotensin converting enzyme 2 (ACE2) with 2019-nCoV S protein was 10~20 times as that with SARS-CoV. ACE2 is expressed expressed in the conjunctiva and cornea of human and rabbit eyes. It can be preliminarily inferred that coronavirus (including 2019-nCoV) has the possibility of invasion by the eye. In addition, glycoproteins of host epithelial cells carrying terminal sialic acid, mainly α-2-3-SA, are distributed in human eye mucosa. And respiratory virus hemagglutinin can effectively bind to sialic acid residues rich in glycoprotein ends. Most people infected with H7 virus have symptoms of conjunctivitis, so it has been suggested that H7 hemagglutinin may also be an important factor in determining whether the virus can invade eyes. Chan et al also demonstrated in vitro cell culture that the H1N1 virus in 2009 pandemic could infect the conjunctival epithelium, and they speculated that patients might be infected with H1N1 through the conjunctival pathway. In another study of Creager in 2018, all influenza viruses tested (including H3N2 H1N1 H7N2 H7N3 Magi H7N7 H7N9 H5N1 virus subtypes) were able to replicate in the monolayer of primary human corneal epithelial cells after aerosol inoculation, and the titer of the virus in corneal cells was determined by the replication ability of the virus itself . Besides, cell located in the interior of the eye (such as retinal cells) are less susceptible to influenza virus than superficial epithelial cells, but they also support replication of high-titer influenza viruses. Factors such as the characteristics of the virus (with or without envelope) and the size of the exposure dose can directly affect the probability of eye transmission. In the study of lower eye exposure dose of influenza virus, the virus was not detected in the subjects’ nasal washings. These studies are a strong warning for front-line health care workers who have to come into contact with a large number of COVID-19 patients every day.
What is particularly noteworthy is that in case 2, the patient had no symptoms of respiratory infection, and her CT manifestations were normal. Except for conjunctivitis, she only presented with non-specific symptoms such as sore throat, dizziness and headache, which brings difficulties to distinguish asymptomatic or mild patients in our clinical work. We believe that the occurrence of this situation is likely to be related to the individual’s autoimmune status. No obvious abnormality was found in cellular immune function (CD3, 4, 8, 16, 19, 56) and humoral immune function (Ig, C3, C4) during her hospitalization. Zhang et al pointed out the value of combined detection of IgM and IgG antibodies in the diagnosis of 2019-nCoV infection. In case 1, both IgM and IgG antibodies were positive, and the protective antibody IgG increased gradually in the later stage. On February 26th, the content of IgG antibody was 90.42 AU/ml, but IgM changed little, which reflected that the patient had passed the acute stage of the disease and entered the recovery stage. During this period, the 2019-nCoV nucleic acid test of the patient in case 1 also showed a negative trend: On February 26th 2019-nCoV nucleic acid was tested negative; On February 28th 2019-nCoV nucleocapsid protein gene negative, 2019-nCoV open reading frame lab positive. The IgM antibody in case 2 stayed negative during hospitalization. On February 19th, the content of IgG antibody in case 2 was 152.08 AU/ml, which was relatively higher. We speculated that although patient in case 2 carried the virus then, she had obtained protective antibodies. However, the nasopharyngeal 2019-nCoV nucleic acid test of case 2 was positive for 3 times after February 19th. In view of this situation, we considered that the possibility of reinfection during the hospitalization period could not be ruled out, so a total of 12 nucleic acid tests were carried out (10 nasopharynx and 2 conjunctival sac). According to the observations in the clinical work, there are still some unstable factors in the detection of 2019-nCoV nucleic acid. Even if the nucleic acid is tested positive, the activity and virulence of the virus cannot be judged. Therefore, even for the patients with elevated IgG, the risk of reinfection and transmission to others should not be ruled out.
In addition, the SAA of patients in both case 1 and 2 increased when they were admitted to hospital, which was consistent with the conclusion of Professor Qu’s team . Among the changes of various inflammatory indexes (SAA, CRP, PCT, WBC) in COVID-19 patients, the sensitivity and change range of serum amyloid A (SAA) were the largest. SAA was observed to significantly increase in the early course of COVID-19. And after the nucleic acid result turned negative, SAA decreased significantly and returned to normal after two negative tests. Recently, the Lancet magazine also published a case analysis of asymptomatic COVID-19 patients of family aggregation, which suggested that the lymphocyte counts and chest CT images of two asymptomatic patients were normal, but the nasopharyngeal swabs were positive for 2019-nCoV nucleic acid. However, other patients in the family had typical clinical symptoms such as fever, sore throat, and muscle soreness with reduced lymphocyte count and abnormal chest CT image, indicating that patients with abnormal immune indicators might be more likely to invade the lungs.
Therefore, we believe that these basic immune indexes and inflammation-related indexes will have further implications for the early diagnosis and monitoring of disease outcome in asymptomatic and mildly infected patients.
The World Health Organization in the “Infection prevention and control during health care when novel coronavirus infection is suspected.” , Particularly emphasizes that medical personnel should wear eye protection tools (goggles) or facemasks, and advises medical personnel not to directly touch any mucosal tissue (eye, nose or mouth) . Most medicines currently available for the treatment of viral conjunctivitis are directed against herpes and adenovirus infections, and infectious diseases of the eye caused by RNA viruses (such as influenza or RSV or coronavirus) lack targeted antiviral medications. Skevaki et al recommend the use of oseltamivir, ganciclovir and other drugs for treatment and prevention during the onset of conjunctivitis symptoms or a history of eye contact .
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