Hi thanks for contacting HCM... Noted your son has nose bleed.... Here mostly it would be anterior nose bleed means artery from anterior nose.... Mostly it will be by trauma as patient is children... Second yes rhinitis allergic or on allergic cause can lead nose bleed... In rhinitis mucosa might dry and so bleeding can occur by rough handling... Coagulation factor defect or abnormality in coagulation can lead it.... So for it PT and APTT can be done... Liver causes also has to be searched by LFT tests.... While bleed just pinch nose with thumb and index finger for 10 minute.... Mostly it will stop bleed .... If still bleed consult doc.you might put cotton ball with medication in nose for it. Avoid sneezing and forceful nose handling. If bleeding continue cautriztion needed. Take care. Dr.parth