Otitis externa

Otitis externa is inflammation of the external auditory canal. The acute form is usually caused by bacterial infection, but it may also be fungal or viral. The chronic form is eczematous and may be atopic or a contact dermatitis. Dermatitis may become infected and the two types of otitis externa can exist together. 

A customer who is buying his holiday requirements tells you that he is flying to his destination, but is terrified because he gets excruciating pain in his ears on the descent before landing and is virtually deaf for hours afterwards. He asks if you can suggest anything to help. 

First statement Ear drops containing gentamicin are never used to treat chronic otitis media. 

Second statement The Committee on Safety of Medicines has stated that topical treatment with ototoxic antibacterials is contraindicated in the presence of a perforation of the eardrum. 

For which of the following should a patient asking for treatment for an ear problem be referred to a doctor without asking any further questions  

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Nitrofurathiazide. 6-Acetylamino-3,-4-dihydro-3-(5-nitro-2-furanyl)-2JT-l,2,4-benzothiadiazine 1,1-dioxide, nitrofurathiazide, is synthesized from 4-acetylanaino-2-aniinobenzenesulfonaniide with 5-nitro-2-furancarboxaldehyde (45). The product has been employed as an antibacterial agent for humans and, in combination with other dmgs, has been used for acute or chronic otitis externa of dogs and cats. 

Sofradex contains dexamethasone, framycetin and gramicidin and is indicated in otitis externa. Canesten contains clotrimazole and is indicated for fungal infections and may be used in otitis externa where a fungal infection is suspected. Nasonex contains mometasone, a corticosteroid, and is used in nasal allergy. 

Q38 Agents that could be recommended for otitis externa include all EXCEPT ... 

Docusate sodium is a preparation used for softening ear wax before removal. Hydrocortisone is a corticosteroid, whereas gentamicin, neomycin and clioquinol are antibacterial agents. Otitis externa may be managed by the use of antibacterial preparations used alone or in combination with topical corticosteroids. 

Otitis externa inflammation or infection of the external ear Otitis interna labyrinthitis, inflammation or infection of the inner ear... 

Acute otitis media (AOM) in children is mostly caused by pneumococci and H. influenzae. It should be differentiated from otitis media with effusion (OME) in which there are no symptoms of acute infection. Furuncles of the nose are caused by S. aureus. It has to be differentiated from diphteria (in unvaccinated children) caused by Corynebac-terium diphteriae and from mononucleosis infec-tiosa caused by Epstein-Barr virus. Chronic ear infections are caused by S. aureus and gram-negative bacillae. Malignant otitis externa in diabetics is caused by P. aeruginosa. 

Patients with leukemia often suffer from infections of the upper respiratory tract before the diagnosis of their haematologic malignancy is made. Chemotherapy for malignancy causes toxic stomatitis and superinfection with yeasts may follow. In patients with diabetes mellitus, malignant otitis externa and fungal sinusitis (mucormycosis) can be life-threatening. 

Oral beta-lactam antibiotics such as amoxycillin, cotrimoxazole or doxycycline for 7-10 days are suitable for the treatment of bacterial sinusitis. Furuncles of the nose should be treated with an anti-staphyloccal drug for 5 days. Standard treatment for streptococcal pharyngitis consists of 10 days of penicillin. Malignant otitis externa responds to high dose quinolone therapy (e.g. ciprofloxacin 750 mg 2 t.d.) administered orally. For parapharyngeal abscess, high dose penicillin plus beta-lactamase inhibitors such as amoxycillin-clavulanic acid can be used. Duration of treatment is guided by clinical and parameters of inflammation, and abscesses often need several weeks to resolve by conservative treatment. 

General luhrication Topical Apply gel to exterior of tube or instrument prior to use. Otitis externa, otitis media Otic Instill 4-5 drops into external ear canal of affected ears. Repeat q l-2h as needed. 

Otitis externa Aural Instill 3 to 4 drops into the ear 3-4 times/day. 

Otitis externa Otic 10 drops into the affected ear once a day for 7 days. 

Some topical anti-infectives contain corticosteroids in addition to antibiotics. There is no convincing evidence that topical corticosteroids inhibit the antibacterial effect of antibiotics when the two are incorporated in the same preparation. In the treatment of secondarily infected dermatoses, which are usually colonized with streptococci, staphylococci, or both, combination therapy may prove superior to corticosteroid therapy alone. Antibiotic-corticosteroid combinations may be useful in treating diaper dermatitis, otitis externa, and impetiginized eczema. 

Acetic Acid Aluminum Acetate (Otic Domeboro) [Astringent/ Anti-infective] Uses Otitis externa Action Anti-infective Dose 4-6 gtt... 

Van Ginkel, C.J., Bruintjes, T.D., and Huizing, E.H., Allergy due to topical medications in chronic otitis externa and otitis media. Clin. Otolaryngol. 20, 326-328, 1995. 

The ototopical antimicrobial preparations stated earlier suffice for most cases of otitis externa and selected cases of chronic suppurative otitis. However, these compounds have a limited effect in certain patients with resistant strains of bacteria, drug-induced allergies, or a tympanic membrane perforation that requires administration into the middle ear space. In the last case, ototopical preparations may cause pain because of the acidic pH or the presence of alcohol. Ototoxicity of neomycin, polymyxin B, and colistin is also of concern, and many otolaryngologists prefer topical ophthalmic preparations.f Ophthalmic preparations are discussed in the article Ocular Drug Formulation and Delivery in this volume. 

Cassisi, N. Cohn, A. Davidson, T. Witten, B.R. Diffuse otitis externa, clinical and microbiologic findings in the course of a multicenter study on a new otic solution. Ann. Otolaryngol. Rhinol. Laryngol. 1977, 86 (Suppl 39). 

Lopez, L. Evens, R.P. Drug therapy of aspergillus otitis externa. Otolaryngol. Head Neck Surg. 1980, 88, 649-651. 

Roest MA, Shaw S, Orton DI. Allergic contact otitis externa due to iodoform in BIPP cavity dressings. Contact Dermatitis 2002 46(6) 360. 

Unilateral earache has been reported in two patients (SEDA-9,134). Excessive cerumen production and otitis externa have also been reported. 

Neomycin is not usually administered parenter-ally to animals because of nephrotoxicity and ototoxicity. Only 3% of a dose of neomycin is absorbed following p.o. administration it is, therefore, used in the therapy of coliform enteritis in small and large animals. It is available as tablets, boluses and water additives, in many different combinations with antibiotics, corticosteroids and anticholinergic agents. It can also be used to decrease nitrogenous waste production by the normal gastrointestinal flora in animals with hepatic encephalopathy. Neomycin is not absorbed through the skin, so it is frequently utilized as the antibacterial constituent in ophthalmic formulations (especially in combination with bacitracin and polymyxin B) and in preparations for the treatment of otitis externa in small animals. 

Otitis externa and otitis media are infections of the external and middle ear respectively and are treated with analgesics (see chapter 16) and antibiotics (see chapter 13). Table 22-2 contains commonly prescribed antibiotics for ear infections. 

Places two drops of alcohol in the ear canal to keep it dry before swimming to prevent otitis externa (swimmer s ear)... 

Mild eczematous otitis externa affecting the pinna can be treated with hydrocortisone cream (see Chapter 27). 

Aluminium acetate is astringent and hygroscopic and produces an acidic environment that is hostile to pathogenic bacteria. Aluminium Acetate (13%) Ear Drops BP can be used as an anti-inflammatory for eczematous otitis externa in the external ear canal. 

Other reports also support a role for bacterial lectins in natural infections. Sialylated glycoproteins, administered orally, protected colostrum-deprived, newborn calves against lethal doses of enterotoxigenic E. coli K99[158]. In a clinical trial in humans, patients with otitis externa (a painful swelling with secretion from the external auditory canal) caused by P. aeruginosa were treated at the site of infection with a solution of galactose, mannose and AT-acetylneuraminic acid. The results were fully comparable to those obtained with conventional antibiotic treatment [159]. 

Ofloxacin interferes with microbial DNA synthesis. It is indicated in the treatment of acnte bacterial exacerbations of chronic bronchitis, commnnity acquired pneumonia, uncomplicated skin and skin structure infections, acute uncomplicated urethral and cervical gonorrhea, nongonococcal urethritis, cervicitis, acute pelvic inflammatory disease, uncomplicated cystitis, complicated urinary tract infections (UTI), and prostatitis cdiV eAhy Escherichia coli. Ophthalmic use for treatment of conjunctivitis and corneal ulcer infections caused by susceptible organisms otic use for treatment of otitis externa, chronic suppurative otitis media in patients with perforated tympanic membranes, and acute otitis media in pediatric patients with tympanostomy tubes. 

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