J Neurosurg 73:962-964,1990
Subarachnoid hemorrhage caused by a fungal aneurysm of the vertebral artery as a complication of intracranial aneurysm clipping Case report WOLFGANG PETER PIOTROWSKI, M.D., PETER PILZ, M.D., AND I-HsING CHUANG, M.D. Departments of Neurosurgery and Neurology, Landesnervenklinik Salzburg, Salzburg, Austria ~" Intracranial aneurysms are an uncommon manifestation of fungal infection. A case is described in which the formation of an aneurysm followed an intracranial intraoperative Aspergillus infection attributable to a long period of preoperative antibiotic medication and immunosuppressive therapy with steroids. KEY WORDS 9 Aspergillus antibiotic therapy 9 steroid
9 aneurysm, fungal
9 aneurysm, mycotic 9 subarachnoid hemorrhage
ONFICK 3 was the first to describe an aneurysm caused by an embolus of infectious particles in 1873. Most such aneurysms develop in the course of bacterial infections, often in connection with endocarditis;4,5.11,12 in rare cases, these aneurysms result from fungal infection: The first case of postinfectious aneurysm of fungal origin was reported by Mahaley and Spock 8 in 1968. The increasing use of corticosteroids and immunosuppressive therapies has led to a rise in fungal infections, especially in patients with reduced resistance, t '2 Case Report
This 40-year-old woman with an unremarkable history (except for states of depression) became unconscious while performing housework. She was transferred by helicopter to our clinic from a regional hospital with the suspected diagnosis of subarachnoid hemorrhage (SAH). She arrived intubated and artificially ventilated. Examination. The patient was unresponsive to pain. Her pupils were moderately dilated with prompt reaction to light. Computerized tomography (CT) of the head demonstrated an SAH with blood in the basilar and the mesencephalic cisterns and overlying the temporal parietal region. In addition, a partially calcified plexus papilloma lay in the right lateral ventricle. Cerebral angiography revealed the source of the hemor962
rhage to be an aneurysm of the left internal carotid artery at the distal part of the subclinoid segment. The remaining vascular segments including the vertebrobasilar system were unremarkable. A C T scan of the lungs showed typical bilateral atelectatic areas at the base of one lung, probably caused by aspiration and hypoventilation before admission; the other lung was unremarkable. Operation. Because of the severity of the SAH (Hunt and Hess Grade IV) and her poor condition, the patient was initially treated conservatively. She was given artificial ventilation for 2 days and received antibiotic therapy, nimodipine (2 mg/hr) and dexamethasone (4 mg/6 hrs), for 21 days. After the disappearance of vasospasm (lasting from the 6th to the 20th day postSAH, as verified by transcranial Doppler ultrasonography), the patient underwent elective surgery. The aneurysm was clipped via a left pterional approach during a 2 89 operation. Postoperative Course. The postoperative course was uneventful. The patient was asymptomatic on the 13th postoperative day and discharged home. Three weeks later (8 weeks after SAH), the patient was readmitted. Her husband noticed some mental changes and decreased activity lasting a few days prior to readmission. On examination she was drowsy and disoriented to time and space, but showed no neurological deficits otherwise. A C T scan of the head showed slight wid-
J. Neurosurg. / Volume 73/December, 1990
Fungal aneurysm due to antibiotic and steroid medication turned hemorrhagic. A C T scan disclosed an intraventricular hemorrhage with blood mainly in the third and fourth ventricles, and some blood in the lateral ventricles. No blood was seen around the clipped left internal carotid artery aneurysm. The patient did not recover from the sequelae of this bleed and died 8 days later.
FIG. 1. Computerized tomography scan, obtained at second admission 8 weeks after subarachnoid hemorrhage, revealing plexus papilloma of the right lateral ventricle and widening of the ventricles.
ening of the lateral ventricles and the third ventricle (Fig. 1). Based on the clinical symptoms and the CT findings, a cerebrospinal fluid (CSF) absorption disturbance was assumed. Ventriculostomy was performed immediately with drainage of the CSF under increased pressure. Examination of CSF showed a total protein value of 74 mg/dl and a white blood cell count of 105 cu mm. Cytological studies revealed granulocytes, lymphocytes, and monocytes in equal parts, with occasional erythrocytes and macrophages. Bacterial cultures of the CSF were negative. During the following 48 hours the patient improved satisfactorily. On the 2nd postoperative day a dramatic deterioration occurred; she su :ldenly lost consciousness, respiratory insufficiency required mechanical ventilation, and the CSF obtained via ventricular drainage had
Neuropathological Findings. Neuropathologicalexamination showed residues of an older SAH with yellow deposits on the meninges of the convexity and a massive recent SAH at the base. Brain weight was 1370 gm. On frontal sections, massive intraventricular hemorrhage was seen with blood in all ventricles. The left posterior cerebral artery arose from the internal carotid artery, where a typical saccular aneurysm 5 m m long was found to be well clipped. The aneurysm was collapsed and partially filled with an older thrombotic mass with fibroblasts and hematoidin pigmentation. Around the clipped aneurysm, abscess formation and massive infiltration with numerous fungal hyphae were seen. The hyphae were quite regular in structure; the septate hyphae branched into two. Microscopic examination of sections stained with hematoxylin and eosin revealed that the fungi were slightly basophilic. The fungi also stained well with periodic acid-Schiff; however, Grocott-silver staining was most revealing. Based on morphological criteria, a diagnosis of Aspergillus was made. A circumscript rupture was found at the main segment of the left posterior cerebral artery, and this area was invaded by fungal hyphae. The rupture site was sealed by fresh thrombus. At the right vertebral artery a pea-sized ruptured "aneurysm" was visible, which was found at histological examination to be a recent rupture of the vessel wall caused by fungal infiltration (Fig. 2). The aneurysm was covered with thrombus. The surrounding hemorrhage penetrated into the surface of the lateral brain stem. The basal meninges showed fresh
FIG. 2. Left: Photomicrograph showing wall rupture of the right vertebral artery and massive hemorrhage. Grocott-silver, x 5.5. Right: Selective enlargement of photomicrograph shown left revealing fungal infiltration of the vessel wall at the site of rupture. Grocott-silver, x 44.
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W. P. Piotrowski, P. Pilz, and I. H. Chuang blood and a marked lymphocytic and plasmocytic infiltration with occasional fungal hyphae. A plexus papilloma was visible at the trigone area of the right lateral ventricle. The mass had extensive calcifications, measured 1.5 cm in diameter, and was adherent to the lateral wall of the lateral ventricle. Cerebellar herniation was present. Postmortem examination of the body revealed no sign of a systemic fungal infection. Discussion
In this case, a typical saccular aneurysm, which had been clearly identified and had given rise to the first SAH, was clipped at the patient's initial admission. In the immediate neighborhood of the clipped aneurysm, fungal abscesses developed and the wall of the left cerebral posterior artery was also infiltrated by fungi. The fungal infection then spread over the basal meninges and invaded the right vertebral artery, causing the fungal aneurysm that led to the final and fatal bleed. As the fungal abscesses were found mainly around the operative site, and as there was no other source for a mycotic infection discovered in the patient, one must assume that the fungal infection occurred postoperatively. Most likely the prolonged preoperative use of antibiotics, in combination with steroid therapy, facilitated the propagation of the Aspergillus infection. The Aspergillus species involved in this case was probably A. fumigatus, of which the spores are commonly found in the environment. The most frequent manifestations of fungal infections of the central nervous system are granulomas, abscesses, and meningitis. 1'3'1~'~2 Usually, aneurysms caused by fungi develop in connection with a fungal meningitis or an adjacent fungal infection. 7'9'w The most c o m m o n organisms are Aspergillus (as in this case), followed by Candida and Phycomycetes. 9 Bacterial aneurysms involve chiefly the peripheral branches of the middle cerebral artery, 4 while fungal aneurysms occur mainly in the large intracranial vessels. 7'9'~4'~5Of the 18 cases reported in the literature, not including ours, 11 (61%) were found at the internal carotid or basilar artery. 6 Conclusions
In no previously published cases is an aneurysm described as a complication of an intracranial intraoperative fungal infection without preexisting fungal disease, either intracranial or otherwise. In this case, it is very likely that infection and propagation of this fungal disease was favored by the lengthy treatment
with dexamethasone and antibiotic agents that preceded the operation. Acknowledgment
The authors wish to thank Erika Rochowanski, M.D., for her advice and assistance in preparing this manuscript. References
1. Adams JH: Parasitic and fungal infections of the nervous system, in Blackwood W, Corsellis JAN (eds): Greenfield's Neuropathology. London: Edward Arnold, 1976, pp 269-291 2. Ahuja GK, Jain N, Vijayaraghavan M, et at: Cerebral mycotic aneurysm of fungal origin. Case report. J Neurosurg 49:107-I 10, 1978 3. Banerji AK, Singh MS, Kak VK, et at: Cerebral aspergillosis. Report of eight cases. Indian J Pathoi Microbioi 20: 91-100, 1977 4. Bohmfalk GL, Story JL, Wissinger JP, et al: Bacterial intracranial aneurysms. J Neurosurg 48:369-382, 1978 5. Frazee JG, Cahan LD, Winter J: Bacterial intracranial aneurysms. J Neurosurg 53:633-641, 1980 6. Hadley MN, Martin NA, Spetzler RF, et al: Multiple intracranial aneurysms due to Coccidioides immitis infection. Case report. J Neurosurg 66:453-456, 1987 7. Horten BC, Abbott GF, Porro RS: Fungal aneurysms of intracranial vessels. Arch Neurol 33:577-579, 1976 8. Mahaley MS Jr, Spock A: An unusual case of intracranial aneurysm, in Smith JL (ed): Nearo-Ophthalmology. St Louis: CV Mosby, Vol 4, 1968, pp 158-166 9. Mielke B, Weir B, Oldring D, et at: Fungat aneurysm: case report and review of the literature. Neurosurgery 9: 578-582, 1981 10. Mohandas S, Ahuja GK, Sood VP, et al: Aspergillosis of the central nervous system. J Neurol Sci 38:229-233, 1978 11. Molinari GF: Septic cerebral embolism. Stroke 3: 1t7-122, 1972 12. Molinari GF, Smith L, Goldstein MN, et al: Pathogenesis of cerebral mycotic aneurysms. Neurology 23:325-332, 1972 13. Ponfick E: Ober embolische Aneurysmen, nebst Bemerkungen fiber das akute Herzaneurysma. Virchows Arch Pathol Anat 58:528, 1873 14. Roach MR, Drake CG: Ruptured cerebral aneurysms caused by micro-organisms. N Engl J Med 273: 240-244, 1965 15. Shimosaka S, Waga S: Cerebral chromoblastomycosis complicated by meningitis and multiple fungal aneurysms after resection of a granuloma. Case report. J Neurosurg 59:158-161, 1983 Manuscript received January 5, 1990. Accepted in final form June 4, 1990. Address reprint requests to: Wolfgang Peter Piotrowski, M.D., Department of Neurosurgery, Landesnervenklinik Salzburg, Ignaz-Harrer-Strasse 79, A-5020 Salzburg, Austria.
J. Neurosurg. / Volume 73/December, 1990