The 15th Biennial Congress of the Pan African Association of Neurological Sciences (PAANS) and the 27th Annual Conference of the Egyptian Society of Neurological Surgeons invited me to deliver a “memorial lecture” at their joint 2002 meeting which was held in Cairo, Egypt in March 2002.
I put the spotlight on the late Ahmed El-Banhawy of Egypt. I spoke on schistosomiasis of the spinal cord (SSC), a subject on which he made immense and landmark contribution to our present knowledge on the presentation and management.
Egypt is celebrated for according respect and recognition to whose who advanced our knowledge of schistosomiasis (bilharziasis). Thus, there is the Theodor bilharz Institute. The granuloma of SSC is already known as El-Banhawy’s granuloma. In continuation of this tradition, I propose that the irregular trifid or three-fingered edges of the upper part of the cord granuloma shown on myelography ought to be called El-banhawy’s sign.
Keywords: Africa, Ahmed El-Banhawy, Schistomiasis, Spinal Cord
Lors du congrès conjoint de la PAANS (15ème) et de la Société Egyptienne de Neurochirurgie qui s’est tenu au Caire en Mars 2002, il m’a été demandé de prononcer une conférence à la mémoire du docteur El-Banhawy.
Mots clés : Afrique, Schistosomiase, Moelle Epinière
The late Professor Ahmed El-Banhawy was one of the earliest members of the Egyptian Society of Neurological Surgeons and a Foundation Fellow of the Pan African Association of Neurological Sciences (PAANS).
He had his neurosurgical training in Oxford, England, Continental Europe and the Montreal Neurological Institute in Canada. By the time he finished, modern neurological surgery had been set up in three Egyptian centres staffed by all – Egyptian neurosurgeons, namely Osman Sorour of Cairo University; Samuel Boctor in Alexandria University and Ibrahim Higazi in Ain Shams University in Cairo. El-Banhawy later succeeded Higazi as the Head of Neurosurgery at Ain Shams University where he later served as Dean of the Faculty of Medicine. He lived at No 10 El-Misaha, Dokki-Giza in Cairo where he treated many of us to simple dinners during our visits to Egypt in the 70’s under the anspices of either PAANS or the International College of Surgeons. An affable gentleman and raconteur, it was always a delight visiting Ahmed and his pleasant family. One of his illustrious trainees in neurosurgery in Egypt was Hussain Abusalih of Sudan. Both of them were present at the 1972 Symposium on Brain tumours held in Nairobi, Kenya at the end of which the Pan African Association Neurological Sciences was formed. El-Banhawy and Abusalih presented a joint paper on “Meningiomas in the Sudan”(2). Abusalih later went into partisan politics in his native Sudan in which he made outstanding success.
I first met El-Banhawy at the second Pan African Congress of Neurological Sciences held in Ibadan Nigeria in January 1970 when he presented papers, with his Egyptian colleagues and trainees on “Peculiar Injuries to Arteries supplying the Brain (9) and on damage of the Carotid Artery as a result of coughing”, “Arterio-venous shunt between the vertebral artery and the sigmoid sinus” and on “False Aneurysms of the middle meningeal artery”. With Sayed EL-Gindi he demonstrated in another paper the place of external drainage of CSF using Pudenz valve in the management of posterior fossa tumour (13). With Hassanein El-Sherif, he presented a paper on his favourite subject “Bilharziasis of the spinal cord” (12). They cautioned that the disease, then considered to be extremely rare, may be more common than thitherto suspected. They presented three cases, one in the upper dorsal spine and 2 in the conus. All were histologically proven at operation, “making this humble series the largest in the world literature”.
On the international scene, Al-Banhawy served as delegate of the PAANS and of the Middle East Neurosurgical Society to the World Federation of Neurosurgical Societies (WFNS). He was a member, for some four years of the head injury committee of the WFNS.
SCHISTOSOMIASIS OF THE SPINAL CORD (SSC)
The most enduring work of El-Banhawy was his seminal landmark contribution to our knowledge of SSC. In his paper of 1978 which was a distillate of his life experience with this disease, El-Banhawy enunciated what he found to be typical of SSC clinically, radiologically and pathologically (11).
The patient is very often a boy or a juvenile aged between 10 and 20 years.
The initial complaint is of low back or girdle or sciatic pain which is soon followed by sphincter disturbance.
Weakness develops in the legs, beginning in one and appearing in the other leg shortly afterwards. The weakness rapidly progresses so that paraplegia is established in few weeks (2).
Myelography shows the characteristic picture of the granuloma which consists of
The three varieties of SSC recognised are the myelitic, the granulomatous and the radicular. El-Banhawy doubted the separate existence of a radicular lesion in his belief that the myelitic and granulomatous lesions each has a radicular component.
AETIOLOGY OF SSC
The cause is the schistosome, a trematode worm. The disease is also called bilharziasis, in honour of Theordor Bilharz who first recognised that this schistosome causes disease (16). The three major species of the parasite are S. mansoni, S. haematobium and S. Japonicum. The last causes brain lesion and is endemic to the Far East. In Africa and parts of the Middle East, mansoni and haematobium flourish in plentitude and are responsible for spinal cord disease.
Three minor species of the parasite encountered in some African countries are S. intercalatum, S. matthei and S. bovis; these have not been reported to cause CNS lesions. The S. mekongi found in the area adjoining the Mekong River is native to Laos and Cambodia and so far has not been associated with any CNS lesion.
BACKGROUND OF NEUROSCHISTOSOMIASIS
Egypt is the cradle of information on the neurological aspects of schistosomiasis. Here in Cairo in 1913 Ferguson (14) reported the presence of schistosoma ova in the CNS in autopsy material. The same Ferguson in 1917 reported the first case of schistosamal myelopathy in an Egyptian who died of chronic bladder disease caused by this parasite (15). We are not sure which specie of the schistosome was responsible as the distinction between mansoni and haematobium was only established in 1918 by Leiper (21). Hence by 1930 it was possible to ascribe the cause of schistosoma myelopathy in a Brazilian resident to S. mansoni.
INCIDENCE OF SSC
About 100 cases of SSC have been reported in the literature (29). In the world, S. mansoni is a more frequent cause of myelopathy than S. haematobium (27). In the review by Scrimgeour and Gajdusek (27) there were 52 case reports of S. mansoni as opposed to 12 of S. haematobium. In Africa, however, S. haematobium is more often responsible than mansoni for myeloradiculopathy (19).
AGE AND GENDER
Comprehensive reviews have shown SSC to be a disease of predominantly young males. The mean age of patients with mansoni myelopathy was 27.7 years and 83 percent were males; the corresponding figures for haematobium myelopathy were 19.7 years and 92 percent male of average age and gender incidence.
REPORTS OF HISTOLOGICALLY PROVEN CASES FROM AFRICA
(a)S. haematobium myelopathy (13 cases) are distributed as follows: 7 from Egypt (Day and Kenawy (8), Bayoumi, (4), El-Banhawy, (10), Gawish, (17), 3 from South Africa (Pepler and Lombard, (23), Bird (5), Cosnett and Van Dellen, (6), Haribhai et al (19), 2 from Nigeria (Odeku et al, (22), Adeloye et al, (3) and one from Zimbabwe (Gelfand) (18).
(b)S. mansoni myelopathy (10 cases). These are distributed as follows: 3 from Egypt El-Banhawy (10), Gawish, (17), 2 from Sudan (Abbott and Spencer), (1), El-Banhawy (10), 2 from Kenya (Dar and Zimmerman), (7), Ruberti and Sai (25) one form Mali (Willemin-Clog et al (30) one from Nigeria (Kerr et al (20) and one from Tanzania (Scrimgeour) (26).
(c)Undetermined Schistosoma cases were reported in seven patients: 2 each from Egypt, Kenya, and South Africa and one from Zimbabwe (26, 27).
(d)Cases in which schistosomal myelopathy was suspected came from Ivory Coast, Ghana, Togo, Malawi, Uganda and Zambia (Scrimgeour and Gajdusek) Suspicion was kindled by clinical features, laboratory investigations, myelographic studies and the good response to schistosomicidal chemotherapy (27).
The clinico-radiological characteristics described by El-Banhawy remain the basis for the diagnosis of SSC. These form the useful cue for diagnosis in areas of the world where this parasitic infestation is endemic, such as Egypt. Where it is rare, a high index of suspicion is a requisite for diagnosis. Hence South African workers in Durban have set up a management protocol to assist in picking up cases of SSC (19).
Computer Scan has improved the radiological diagnosis. When the lesion is a granuloma, computer assisted myelography demonstrates the mass in the lower spinal cord or at the conus together with the irregular swellings of the nerve roots forming the cauda equina (19, 20). When the lesion is a myelitis, the radiographic picture on the computer assisted myelography is normal, with the infected nerve roots showing beaded appearance.
Magnetic Resonance Imaging (MRI). The few reports of MRI in SSC show that the investigation confirms the findings of assisted myelography; it may also show cord atrophy in patients with necrotic myelitis who do not respond well to treatment.
The best course of treatment is a combination of decompressive laminectomy and the adminstration of schistosomicidal drugs.
In 1971, El-Banhawy recommended laminectomy as an adjunct to the management of patients with acute paralegia and spinal block (10). Experience of later workers revealed a few riders to the place of laminectomy. The operation, alone, does not change the preoperative neurological status of the patient; clinical improvement starts with the post operative use of appropriate chemotherapy (20, 29).
Biopsy of the mass at operation is enough; it confirms the diagnosis and rules out other disease, neoplasms in particular, which mimic SSC. Aggressive removal of the granuloma should be avoided as it worsens the neurological status of the patient (Adeloye et al) (3).
The drug of choice is praziquantel (PZQ) which usually produced clinical improvement within a few days of its commencement.
The drug kills the adult female worm, leading to cessation of ova production and consequent inflammatory response.
Other drugs have been used. The first was sodium animony tartrate which was later quickly abandoned because of its toxicity and the need to give it by intramuscular or intravenous injection.
Oxamniquine and niridazole (ambilhar) are also used. PZQ and oxamniquine are most effective against mansoni infection; PZQ or metrifonate are recommended for haematobium infection; niradazole is effective against both parasites.
There are reports in the literature of the use of coricosteroids which act by reducing inflammatory response, granuloma formation and tissue destruction. Nevertheless the role of steroid in treating SSC remains controversial. Cases of suspected SSC treated with chemotherapy alone and with satisfactory clinical improvement have also been reported.
I.Spinal cord neoplasm. Neuro-radiology may provide evidence suggesting cord neoplasm; findings at laminectomy and biopsy help to confirm diagnosis.
II.Transverse myelitis of SSC affects the lower cord whereas other causes of transverse myelitis affect the mid-thoracic region (Tyler), (28).
III.HIV myelopathy has emerged recently as an imitator of many diseases including SSC.
V.South African workers have suggested that in Africa, when the doctor at the district or general hospital suspects SSC a chemotherapeutic trial with PZQ should be started at once and the patient referred to a neurological centre for detailed investigation and management while the drug treatment continues (Haribhai et al) (19).
The diagnostic features and management principles of SSC enunciated by El-Banhawy of Egypt are still as reliable and relevant today as they were two decades ago.
Schistosomiasis (Bilharziasis) is known among the laity as snail fever. It has plagued mankind in general and Egyptians in particular for millions of years. In some villages of the Nile delta, 9 out of 10 people are infected. Consequently, Egyptians have given respect and recognition to any worker who had played any significant role in combating this infestation. Thus the centre in Egypt devoted to research into this disease is called Theodor bilharz Research Centre in honour of his discovery of the worm that causes bilharziasis. In Egypt the granuloma of the cord lesion is now known as El-Banhawy’s granuloma. In continuation of the appropriate tradition of honouring workers on SSC, I recommend that the myelographic picture of 3 fingered (trifid) upper end of the granuloma be called El-Banhawy’s sign.