Thursday, November 21, 2013

CMJ: Varied Clinical Presentations Of H7N9



# 7997



While we’ve only seen a limited number H7N9 infections in China, as studies are published we are learning more about the different ways this virus manifests in patients, with some  experiencing relatively mild illness, while others progress to ARDS and even death.


Last month in PLoS One: Epidemiological & Clinical Description Of 6 H7N9 Cases – Shanghai we looked at the course of illness among a half dozen patients treated at Fifth People’s Hospital of Shanghai, as well as a study on Hematological & Biochemical Abnormalities In H7N9 Patients in the Journal of Medical Virology.


Today, a pair of reports from the Chinese Medical Journal (CMJ) that discuss four unusual H7N9 presentations (h/t @Ironorehopper), including both cardiovascular and neurological complications.


First stop, a brief letter describing a non-typical presentation in an 87 year-old man, who initially (April 4th) complained of loss of appetite and strength but no fever, cough, or expectoration.  Chest x-rays on the 6th indicated some lung inflammation, but due to his symptoms a bacterial, not a viral cause, was suspected.  He admitted to the hospital and was placed on antibiotics (cefuroxime).


Five days into his illness, he developed dyspnea (shortness of breath) and an elevated temperature, and on April 10th deteriorated further. Influenza was finally suspected, and he was started on oseltamivir and levofloxacin, and a decision to test for H7N9 was made. 


Despite ICU treatment, and a transfer to specialized hospital, the patient died on April 21st.


The authors write:

This case history serves to remind us that we need timely use of antiviral treatment, even for the patients whose clinical manifestations are not typical but whose lung inflammation may be developing rapidly. Careful clinical observation needs to be carried out so that appropriate treatment can begin as early as possible and progression culminating in death is minimized


The entire letter may be read at:


Chinese Medical Journal 2013;126(22):4399-4399
A case with non-typical clinical course of H7N9 avian influenza

ZHENG Yu-fang, CAO Ye, LU Yun-fei, XI Xiu-hong, QIAN Zhi-ping, Lowrie Douglas, LIU Xi-nian, WANG Yan-bin, ZHANG Qi, LU Shui-hua and LU Hong-zhou



A second, more detailed report also appears in the Chinese Medical Journal, that looks at three H7N9 cases, and the variability in their clinical presentation – including neurological and cardiovascular manifestations.


The authors write:

In this report, the initial clinical manifestations of three confirmed cases are summarized. Two of the patients were in critical condition. In addition, two of the patients experienced changes in mental status, one of which was believed to be the first published case with Brugada syndrome associated with H7N9 infection in China. We suggest that this H7N9 virus causes various signs and symptoms in the early stages of infection.


We’ve seen reports of neurological complications with influenza in the past (see Neurologic Manifestations of Pandemic (H1N1) 2009 Virus Infection), but the bulk of these cases have involved children or adolescents. And we’ve also seen studies that suggest that influenza can induce cardiogenic changes as well (see  Another Study Links Heart Attacks & Influenza). 


So while these H7N9 cases are the first to be documented in China with these complications, their existence is not without precedence.


Follow the link below to read the complete case histories of all three patients (age range 39 to 69), two of whom survived.  For those unfamiliar with Brugada syndrome, is a relatively recently (1992) recognized condition that is characterized by an abnormal EKG that signifies an increased risk of sudden cardiac arrest.


Chinese Medical Journal 2013;126(21):4194-4196
Clinical variability in onset of influenza A (H7N9) infection

WANG Shu-ying, REN Shu-hua, HUANG Mei-xian, YU Dao-jun, SHEN Qiang, ZHAO Hong-feng, LÜ Qiao-hong and QIAN Shen-xian


Based on these case reports, patients with H7N9 influenza virus infection from symptom onset to laboratory confirmation showed variable findings in clinical manifestation. Patients with H7N9 infection present variable symptoms: fever, cough, phlegm production, hemoptysis, chest tightness, diarrhea, and disturbance of consciousness. Detection of the nucleic acids of H7N9 virus in the throat swab specimens may show negative results in the early stage. Clinicians should remain vigilant to the possibility of H7N9 infection associated with neurological and cardiovascular complications, because the novel virus may unmask some underlying diseases. Documentation of



Four cases out of a pool of just over 130 doesn’t really tell us a lot about the incidence of these atypical findings, but it does serve to remind us that a severe influenza infection can impact our physiology in many ways, and can exacerbate many previously existent (even if not previously diagnosed) conditions.

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