The lymph glands behind the angle of the jaw enlarge and become tender, and may suppurate from superadded infection.  There is pain on swallowing, and often earache; and the patient speaks with a nasal accent.  He becomes weak and anaemic, and loses his appetite.  There is often albuminuria.  Leucocytosis is usually well marked before the injection of antitoxin; after the injection there is usually a diminution in the number of leucocytes.  The false membrane may separate and be cast off, after which the patient gradually recovers.  Death may take place from gradual failure of the heart’s action or from syncope during some slight exertion.

Laryngeal Diphtheria.—­The disease may arise in the larynx, although, as a rule, it spreads thence from the pharynx.  It first manifests itself by a short, dry, croupy cough, and hoarseness of the voice.  The first difficulty in breathing usually takes place during the night, and once it begins, it rapidly gets worse.  Inspiration becomes noisy, sometimes stridulous or metallic or sibilant, and there is marked indrawing of the epigastrium and lower intercostal spaces.  The hoarseness becomes more marked, the cough more severe, and the patient restless.  The difficulty of breathing occurs in paroxysms, which gradually increase in frequency and severity, until at length the patient becomes asphyxiated.  The duration of the disease varies from a few hours to four or five days.

After the acute symptoms have passed off, various localised paralyses may develop, affecting particularly the nerves of the palatal and orbital muscles, less frequently the lower limbs.

#Diagnosis.#—­The finding of the Klebs-Loffler bacillus is the only conclusive evidence of the disease.  The bacillus may be obtained by swabbing the throat with a piece of aseptic—­not antiseptic—­cotton wool or clean linen rag held in a pair of forceps, and rotated so as to entangle portions of the false membrane or exudate.  The swab thus obtained is placed in a test-tube, previously sterilised by having had some water boiled in it, and sent to a laboratory for investigation.  To identify the bacillus a piece of the membrane from the swab is rubbed on a cover glass, dried, and stained with methylene blue or other basic stain; or cultures may be made on agar or other suitable medium.  When a bacteriological examination is impossible, or when the clinical features do not coincide with the results obtained, the patient should always be treated on the assumption that he suffers from diphtheria.  So much doubt exists as to the real nature of membranous croup and its relationship to true diphtheria, that when the diagnosis between the two is uncertain the safest plan is to treat the case as one of diphtheria.

In children, diphtheria may occur on the vulva, vagina, prepuce, or glans penis, and give rise to difficulty in diagnosis, which is only cleared up by demonstration of the bacillus.

#Treatment.#—­An attempt may be made to destroy or to counteract the organisms by swabbing the throat with strong antiseptic solutions, such as 1 in 1000 corrosive sublimate or 1 in 30 carbolic acid, or by spraying with peroxide of hydrogen.