Influenza A Infection Unmasking an Underlying Mitral Valve Stenosis in a 19-Year-Old Boy
A 19-year-old male patient presented to the emergency with complaints of high-grade fever since 8-12 days, not associated with chills, along with difficulty in breathing and hemoptysis since one day. On admission his temperature was 102΀F, blood pressure (BP) = 94/58 mm of Hg, heart rate (HR) = 152 bpm, SpO2 = 88% with oxygen support. On examination the patient was conscious, tachypneic, dyspneic and was using accessory muscles for breathing. Bilateral coarse crepitations were present and the air entry was reduced bilaterally. Cardiac examination revealed a loud first heart sound, tachycardia; no murmur was, however, audible. Neck veins were engorged and abdominal examination revealed hepatomegaly 4 cm below the costal margins. Routine blood tests, Arterial Blood Gas analysis and a throat swab were sent for examination. Chest X-ray revealed B/L homogenous opacities involving middle and basal lung fields []. ABG showed pH = 7.40, pCO2 = 22 mm of Hg, pO2 = 56 mm of Hg, HCO3 = 23 meq/l. The patient was given Bi-PAP support and empiric treatment was started keeping a possibility of viral pneumonitis among the differentials. Complete blood count (CBC) showed a Total Leucocyte Count of 8820/mm3, DLC = P85%, L13%, E2%, Hb = 11.8g/dl, Platelet count = 94000/mm3, Blood urea = 38 mg/dl, Sr. creatinine = 0.9 mg/dl, Sr.K+ = 3.4 meq/l, Sr. Na+ = 140 meq/l, Sr. bilirubin = 4.2 mg/dl, (direct = 2.1 mg/dl, indirect = 2.1 mg/dl). Total Sr. protein = 4.9 g/dl, Sr. albumin = 2.3 mg/dl, Sr. globulin = 2.6 mg/dl, AST = 116U/L, ALT = 48U/L, Sr. alkaline phosphatase = 91 U/L and CPK-MB = 28 ng/dl. A 2D-ECHO showed severe mitral valve stenosis (valve area = 0.93 cm2), moderate tricuspid regurgitation, moderate pulmonary hypertension and a dilated right and left atrium. The throat swab culture was positive for Influenza A. The patient gradually improved over a period of ten days and was subsequently referred to cardiothoracic surgery for management of mitral stenosis.