The external auditory meatus is swollen closed, very tender, not erythematous, and usually without any evidence of otorrhea. There is often a tender infra-auricular lymphnode present, and the postauricular crease is red and a little swollen. The presence of an enlarged and tender postauricular node will sometimes prompt the referring physician to send the patient to you with a diagnosis of "mastoid."
Treatment is directed a relieving the patient's pain, by prescribing opiates (codeine, and occasionally, meperidine) and inserting a wick moistened with an antimicrobial/corticosteroid eardrop. The patient is instructed to keep the wick moist with the prescribed drops, and to remove the wick in 2 days, returning to your office a day later for followup exam, and most importantly, to begin a program of prophylaxis.
It has been my experience that if the patient fails to return for the second phase of the treatment, prophylaxis, he will most assuredly blame you for the inevitable reoccurrence of his ear infection.
In severe cases, a diminishing dose of prednisone (Medrol dosepak) will accelerate the resolution of the inflammation and give the patient relief of his pain within twelve hours of the first dose. The prednisone is supplemented by a prescription for a broad spectrum orally administered antibiotic, to reduce the risk of the infection spreading beyond the ear canal.
Physical presentation is that of a red canal, somewhat swollen and tender, with white, black, gray, or brown debris deep within the canal, usually right up against the drum, having been driven there by the patient's attempts at cleaning the canal with q-tips. Sometimes the fungal growth can be mistaken for the cotton tip of a q-tip itself.
The disorder fails to respond to the usual antibacterial topical medications, and that is often the physician's first clue to the diagnosis. Laboratory identification of the fungi is of questionable benefit, for antifungal sensitivity tends to be inconsistently related to fungal species.
Lucente FE (Otolar. Clin N.A. v20 no6 Dec 1993 995-1006) collected 15 species of yeast and fungi from patients with external otitis during the course of one year. He obtained antifungal sensitivities on these specimens, using clotrimazole, nystatin, tolnaftate, amphotericin B, miconazole, natamycin, and flucytosine. Clotrimazole consistently had the largest zone of inhibition aginst common fungi. Nystatin, amphotericin B, miconazole, and natamycin were also effective, but to a lesser extent. Only clotrimazole and miconazole showed antibacterial effects against Staphylococcus epidermidis and aureus.
The common otic preparations (Vosol, Cortisporin, 95% ethyl alcohol), were generally not effective in vitro. Thimerasol (Merthiolate) was effective against all yeasts, fungi, and bacteria except enterococci (but the FDA has forbidden its use and I have to get it from Mexico.) Thimerasol was the only nonantimicrobial agent showing good effectiveness.
Some agents are effective because of their action on host tissues rather than any intrinsic fungistatic properties. Keratolytic agents may treat or prevent fungus infections by encouraging desquamation of infected epidermis.
Another study (Lawrence TL - Lscope 88;1755-1760: 1978) showed that thimerasol and metacresyl acetate (Cresatin) were effective in vitro, while clotrimazol and nystatin were ineffective.
Lucente has sometimes had to use systemic antifungals such as ketoconazole and fluconazole in addition to topical treatment, but he recommends obtaining the help of an infectious disease specialist who is familiar with the side effects of these drugs. He suggests a treatment protocol for recurrent itching of the ears, which is rather involved, and he cautions against using certain of the antifungals in ears in which there is a perforation of the eardrum. Metacresyl acetate and acetic acid preparations, both of which contain propylene glycol, have caused profound hearing loss in guinea pigs (47 dB); clotrimazol to a lesser extent (17dB), and tolnaftate not at all.
Remember to use your dermatologist for difficult cases, especially for identification of specific fungi and suggestions for appropriate treatment.
The patient is usually brought in by a younger relative, concerned about the possibility of "infection" and a ready witness to his habit of continually poking things in his ears. Treatment is based on convincing the patient to quit "cleaning" his ears, and clearing the Ps. aeruginosa infection with a topical preparation. Followup examination is essential, for reinforcement of your instructions to the patient, and for control of the itching which accompanies the condition and probably precipitated the chronic infection.
It is sometimes difficult to distinguish this condition from psoriatic or seborrheic disease, except that eczematoid external otitis exists without concommitant lesions elsewhere. Treatment with hydrocortisone cream initially, and PSS ointment prophylaxis, is almost always effective. If treatment fails, or if the lesion extends beyond the cavum conchae, consultation with a dermatologist is a good idea. The literature seems to suggest that the condition represents a chronic form of otomycosis, but evidence for this is unclear. In any event, the keratolytic action of salicylic acid can be expected to render the outer layers of the epithelium less hospitable to fungal growths.
These agents are most active against aerobic gram negatives bacilli, and Ps. aeruginosa is very susceptible to ciprofloxacin. The activity of quinolones against gram positive organisms is more variable. Cipro is moderately active against staphylococci, including methicillin-resistant S. aureus. Recently, however, resistance of staphlyococci to Cipro has increased, and resistance emerges readily during treatment with Cipro alone. Many hospitals report that more than 90% of MRSA strains are resistant to Cipro. Resistance has also been reported in occasional strains of Ps. aeruginosa.
The fluoroquinolones display linear pharmacokinetics and reach peak serum concentrations 1 to 3 hours after oral administration. Food delays absorptions and causes lower and later serum concentration peaks. In general quinolones have long half lives and are not extensively bound to serum proteins.
Studies of ciprofloxacin in gram negative osteomyelitis have reported 75% cure rates with an oral dose of 750 mg. b.i.d. but a rise in the MIC of several quinolones against Ps. aeruginosa has been seen during therapy.
For malignant external otitis the customary treatment has been long-term IV antibiotic therapy. Recent studies have demonstrated a cure rate of about 90% in patients treated with ciprofloxacin, making it the treatment of choice for this infection.
The most common side effect is GI toxicity, noted in about 3 to 7% of patients. Antibiotic-induced colitis had been reported but is rare. CNS effects occur in about 1 to 4%, with more than 1% suffering serious complications including hallucinations, depression, and seizures. Thes effects may be seen after only a few days of therapy.
Published reports, however, indicate that the therapeutic efficacy of azole anitmycotic agents such as clotrimazole, miconazloe and ketoconazole against various forms of aspergillosis is highly questionable. The antifungal effects are inconsistent and there are no large scale trials of these drugs. Fluconazole and Itraconazole may offer greater promise, however.
Amphotericin B was found to be a useful alternative in the therapy of aspergillis otomycosis when applied topically as a 3% solution. With other antibiotics such as oxytetracycline-polymyxin, a 70% cure rate was achieved.
It can occur as a primary acute or chronic myringitis, or as a sequel to acute diffuse external otitis or a perforation of the eardrum. Proteus and Psuedomonas species are the most commonly cultured organisms, similar to the flora of otitis externa and chronic otitis media. In short, there is no evidence that any particular type of bacterial or fungal infection is associated with granular myringitis.
Inflammation is generally chronic, and confined to the outer epithelial and underlying fibrous layers of the drum. These layers become replaced by a proliferating granulation tissue, beginning as a localized patch, which may extend over the surface of the drum. The predominant symptom is scanty foul-smelling otorrhea. Many patients are asymptomatic, without pain or significantly diminished hearing. There may only be a feeling of fulness in the ear. The tympanic membrane is usually obscured by purulent discharge with the granulation tissue peeping through. It lacks the mucous quality of otorrhea from an otitis media with perforation of the TM. In granular myringitis, there is no perforation to be found, whether by visual, pneumatic, or tympanometric examination. The rest of the TM is remarkably normal although there may be one or two dilated feeding vessels supplying the granulation tissue. Further, the skin of the canal and the external meatus is free of any inflammatory reaction.
Treatment generally includes careful and repeated cleaning of the surface of the eardrum, with application of anti-Psuedomonal medication supplemented by a corticosteroid. Failure to resolve suggests a fungal etiology, and insufflation of clotrimazole powder over the surface of the drum has proved successful. There is rarely an indication for cauterization of the granulation tissue, for one risks creating a perforation of the drum where before there had been none. One author recommends only a 0.5% solution of formalin applied to the granulation for no more than 1 or 2 minutes.
Treatment is directed at relieving pain by mild narcotics, and at precluding a common sequel, acute otitis media, by prescribing an oral antibiotic preparation, typically an erythromycin, based on the assumption that Mycoplasma pneumonia is implicated in the disease.
Rarely, the patient will develop a persistent middle ear effusion, and even more rarely, will complain of vertigo during the weeks following the episode of ear pain and drainage. Typically, however, recovery is complete and rapid, without recurrence or sequellae.
Otherwise, treatment is directed toward the likely responsible organisms, Ps. aeruginosa, and beta-hemolytic streptococcus, and should be vigorous and prompt. Hospitalization and intravenous administration of antimicrobials is to be considered if oral doseage fails to evoke rapid improvement.
The pain is typically constant, deep, unremitting, and disruptive of nocturnal repose. It awakens the patient from sleep, and is controlled only with difficulty. If it persists for more than a week, and if the patient is elderly, diabetic, or immunocompromised, malignant external otitis must be presumed.
Treatment has in the past required intravenous administration of anti-psuedomonal antimicrobials, while watching for symptoms of the onset of osteomyelitis of the temporal bone. Treatment of osteomyelitis of the skull base is to be left for another lecture. It is the earliest stage of the disease of malignant external otitis which concerns us today. In past years I have treated a few cases with intramuscular colistimethate 150 mg. IM q 12 hours, supplemented with Colimycin S otic drops, being careful to watch for the side effects of this drug, which include renal impairment and neurologic symptoms such as circumoral paresthesias and disequillibrium. Currently, oral ciprofloxacin has been used in doses of 750 mg. q 12 hours with success in up to 90% of cases. One must remember, however, that ciprofloxacin has not been approved for patient under 18 years of age, for pregnant or lactating women. Also, serious, even fatal reactions have been reported with concurrent administration of theophylline (cardiac arrest, seizure, status epilepticus, and respiratory failure.) Psuedomembraneous colitis is another reported adverse effect of this drug.
For those who swim, or who allow water to enter their ear canals when showering I recommend a preparation called Swimear, available in 2 oz. bottles at most drugstores, and consisting of isopropyl alcohol 95% in anhydrous glycerin, and costing $3.50. For those who experience discomfort upon instilling alcohol into the ear canal, I suggest Star-otic, a 1/2 oz. bottle containing modified Burow's solution (aluminum acetate, acetic acid, and boric acid in propylene glycol, costing $4.00. Both of these are available without prescription.
A somewhat simpler but equally effective treatment for retained water in the ear canal is 95% ethyl alcohol, costing $4.29 for 240 ml, $7.69 for 480 ml, and $17.00 per liter, available at package stores and sold under the name of Everclear. The disadvantage, of course, is that the patient may find a use for this preparation other than otic prophylaxis. ( While on the subject of cost of medications, a 5 ml bottle of gentamicin ophthalmic costs $12.00 and a 10 ml bottle of generic cortisporin otic drops costs $16.00
All patients recovered from acute diffuse otitis externa, as well as those with chronic eczematoid external otitis should be taught to insert PSS ointment (phenol, sulfur precipitate, salicylic acid; 3% of each, in petrolatum 120 gm.) twice daily, and oftener as needed for itching. I teach them to apply it with the back of the little fingernail, just at the orifice of the ear canal, and to massage the tragus briefly and gently, to spread the preparation. Under no circumstances are they to apply it with Q-tips. Often I will direct the pharmacist to dispense two such jars of ointment, one for the home, the other for the office, toolbox, purse, or briefcase. This has had dependably good effect in preventing recurrences of the acute form of the disease, and gives prolonged relief from itching. For those few patients who have not sufficiently recovered from the acute inflammation, and in whom the PSS ointment causes discomfort, I recommend hydrocortisone cream for a week or two, then back to the PSS ointment, to control itching (and to prevent the patient from being driven to scratching his ear again.)
Discussion by James R. B. Hutchinson, M.D., Atlanta, Georgia
Cresatin was a favorite medication, mainly due to its wonderful medicinal aroma. Merck removed it from the market years ago when the FDA said there were no studies to show efficacy. Merck said that since their sales were only 30 gallons worldwide, it was not worth doing studies on it. I found that cleaning, cortisone, and topicals were usually effective. The most unusual treatment of which I am aware was that used as a preventive by the late Lloyd Storrs of Lubbock, Texas. He collected earwax from his patients and used it on those lacking sufficient wax. After recovery from infections this was often the case. He claimed that it was effective.
Lucente, Frank E.: Otolar. Clin. N.A.; 26:6; December 1993; 995-1006 (fungal infections of the ear)
St. Georgiev, Vassil: Respiration; 59: 303-313; December 1992 (azoles and other antifungals)
Stoney, Philip et al.; Jour. Otol.; 21:2; 1992; 129-135 (granular myringitis)
Sable, Carole A. et al.; Geriatrics; 48:6; 41-51; June 1993 (fluoroquinolones)
Linstrom, C. J., and Lucente, F. E. in Bailey, B. J. "Head and Neck Surgery - Otolaryngology" Ch. 117; Lippincott; 1993 (outstandingly thorough and up-to-date review of the entire subject)
Smith P. G. and Lucente, F.E. in Cummings, C. W. "Otolaryngology - Head and Neck Surgery" Ch. 153; C.V. Mosby Co.; 1986 (treatment algorithm for necrotizing ("malignant") otitis media)