Der seltene Fall einer Otitis externa maligna beim Nichtdiabetiker

Abstract

One case of malignant external otitis in a non-diabetic patient is presented. Malignant external otitis is a rare but severe bacterial infection, caused by Pseudomonas aeruginosa, predominantly in elderly diabetic patients. The process starts in the external auditory canal and after crossing the cartilaginous-osseus junction invades the connective tissue, cartilage, bone, and nerves of the temporal bone and the surrounding parts of the base of the skull. The clinical syndrome is a severe, painful inflammation of the external auditory canal with edematous obstruction of the external canal and typical granulation tissue in the canal wall. Diagnostic criteria are pain, edema, exudate, granulations, microabscess, diabetes, old age, identification of Pseudomonas aeruginosa, and even cranial nerve involvement. Further important criteria are failure of local treatment and a positive Tc-99 scan demonstrating osteomyelitis of the temporal bone as a sign of connective tissue, cartilage, and bone invasion. In most cases there is also a positive radiograph or HR-CT of the base of the skull. Except for sequestrations, surgical treatment in malignant external otitis is impractical because of the deep penetration into the base of the skull and the lack of demarcation lines in this diffuse pathological process. Nowadays long term i.v. antibiotic therapy is preferred. In our case we applied Ceftazidim (Fortum) 2 g for 12 weeks twice a day. After this period the patient was completely cured. Our case demonstrates that malignant external otitis should be considered even in non-diabetic patients.

Osteomyelitis of the Temporal Bone: Terminology, Diagnosis, and Management

“…The other causes in our series were malignant external otitis, mastoiditis, tuberculosis, malignancy of the middle ear, and fracture of the temporal bone. Although classically described in elderly diabetic patients, isolated cases have been reported in a small number of nondiabetic patients, 12 particularly in children who are immunocompromised due to malignancy, malnutrition, and severe anemia. 9 In the recent past HIV and acquired immunodeficiency syndrome were frequently reported as a predisposing factors for osteomyelitis of the temporal bone.…”

“…Schweitzer 14 listed warning signs of temporal bone osteomyelitis such as (1) deep pain (temporal, parietal, postauricular, retroorbital); (2) intermittent foul otorrhea and spiking fever; (3) preauricular cellulites; (4) woody induration of pinna; (5) chronic mastoid cutaneous fistula; (6) fibrotic mastoid granulation tissue; (7) intermittent facial twitching suggestive of facial canal dehiscence, and (8) persistent leukocytosis and an elevated sedimentation rate. Anderhuber et al 12 suggested the following diagnostic criteria: pain, edema, exudate, granulations, microabscess, diabetes, old age, identification of P. aeruginosa, and even cranial nerve involvement. The most common symptoms in our series were ear discharge and pain.…”

Otitis externa necroticans

“…Betroffen sind dabei in erster Linie ältere Männer mit Diabetes mellitus [12,14,18]. Allerdings sind in Abweichung von der Definition der Erkrankung auch Fälle bei Nichtdiabetikern mit Immundefekten beobachtet worden [1,29,30].…”

“…Dieser Keim produziert Exotoxine und verschiedene Enzyme, die neben ausgedehnten Nekrosen auch eine Vaskulitis hervorrufen und damit die Phagozytose entscheidend behindern. Dies hat zur Folge, dass im Gegensatz zu anderen entzündlichen Prozessen, die meist mit einer Hyperämie einhergehen, bei der Otitis externa necroticans ein nekrotisches, schlecht perfundiertes Entzündungsareal resultiert [1,5,7,12,21].…”

Otitis externa necroticans

“…Betroffen sind dabei in erster Linie ältere Männer mit Diabetes mellitus [7]. Allerdings sind in Abweichung von der Definition der Erkrankung auch Fälle bei Nichtdiabetikern mit Immundefekten beobachtet worden [1,22]. Der Krankheitsprozess nimmt in der Regel seinen Ausgang von der Haut des äußeren Gehörgangs, breitet sich von dort über das subkutane Gewebe in den Knorpel und schließlich in den Knochen aus.…”