Neuroschistosomiasis due to Schistosoma mansoni: a review of pathogenesis, clinical syndromes and diagnostic approaches

Abstract

SUMMARYNeuroschistosomiasis (NS) is the second most common form of presentation of infection by the trematode, Schistosoma mansoni. Granulomatous inflammatory reaction occurs as a result of schistosome eggs being transmitted to spinal cord or brain via the vascular system, or by inadvertent adult worm migration to these organs. The two main clinical syndromes are spinal cord neuroschistosomiasis (acute or subacute myelopathy) and localized cerebral or cerebellar neuroschistosomiasis (focal CNS impairment, seizures, increased intracranial pressure). Presumptive diagnosis of NS requires confirming the presence of S. mansoni infection by stool microscopy or rectal biopsy for trematode eggs, and serologic testing of blood and spinal fluid. The localized lesions are identified by signs and symptoms, and confirmed by imaging techniques (contrast myelography, CT and MRI). Algorithms are presented to allow a stepwise approach to diagnosis.

Schistosomiasis of the spinal cord: report of 5 cases from Sudan

“…Lesions in the spinal cord are most common in the lumbar and lower thoracic parts [12]. It is believed that the eggs reach the cord either as a result of embolization through the vertebral venous plexus of Batson or they may be deposited locally by ectopic worms in the vicinity of the cord [11,12]. We have shown in serial sections that the eggs appeared to reach the cord via the Virchow-Robin space.…”

“…Schistosomal myelopathy tends to occur early after infection and is more likely to be symptomatic than cerebral schistosomiasis. Spinal schistosomal disease causes acute or subacute myelopathy that may be accompanied by polyradiculitis, bowel or bladder dysfunction, paraparesis, paraplegia, lumbosacral pain and sensory disturbances [11]. Lesions in the spinal cord are most common in the lumbar and lower thoracic parts [12].…”

Neuroschistosomiasis mansoni

“…Thus, the 3 stages of the granulomatous reaction (necrotic-exudative, productive, and fibrotic) are strictly dependent on the evolution of the immunologic response and the interaction between the host and the pathogen. 23,40 Recently, chemokines, especially CCL3/MIP-1a, have been proposed to play an important role in hepatosplenic human schistosomiasis. They have also been studied in several human diseases that affect the CNS such as infectious meningitis, demyelinating neuropathies, inflammatory myopathies, and multiple sclerosis.…”

A bilateral foot drop due to neuroschistosomiasis

“…Currently, more than 200 million people worldwide are affected. In Brazil, it is estimated that between 10 and 12 million people have schistosomiasis mansoni [1]. The conus and cauda equina are the most common sites of involvement of neuroschistosomias, associated with S. Mansoni and S. Japonicum.…”