Radiculomyelitis complicating acute haemorrhagic conjunctivitis. A clinical study

The leptomeninges as a critical organ for normal CNS development and function: First patient and public involved systematic review of arachnoiditis (chronic meningitis)

BACKGROUND & IMPORTANCE

This patient and public-involved systematic review originally focused on arachnoiditis, a supposedly rare "iatrogenic chronic meningitis" causing permanent neurologic damage and intractable pain. We sought to prove disease existence, causation, symptoms, and inform future directions. After 63 terms for the same pathology were found, the study was renamed Diseases of the Leptomeninges (DLMs). We present results that nullify traditional clinical thinking about DLMs, answer study questions, and create a unified path forward.

METHODS

The prospective PRISMA protocol is published at Arcsology.org. We used four platforms, 10 sources, extraction software, and critical review with ≥2 researchers at each phase. All human sources to 12/6/2020 were eligible for qualitative synthesis utilizing R. Weekly updates since cutoff strengthen conclusions.

RESULTS

Included were 887/14286 sources containing 12721 DLMs patients. Pathology involves the subarachnoid space (SAS) and pia. DLMs occurred in all countries as a contributor to the top 10 causes of disability-adjusted life years lost, with communicable diseases (CDs) predominating. In the USA, the ratio of CDs to iatrogenic causes is 2.4:1, contradicting arachnoiditis literature. Spinal fusion surgery comprised 54.7% of the iatrogenic category, with rhBMP-2 resulting in 2.4x more DLMs than no use (p<0.0001). Spinal injections and neuraxial anesthesia procedures cause 1.1%, and 0.2% permanent DLMs, respectively. Syringomyelia, hydrocephalus, and arachnoid cysts are complications caused by blocked CSF flow. CNS neuron death occurs due to insufficient arterial supply from compromised vasculature and nerves traversing the SAS. Contrast MRI is currently the diagnostic test of choice. Lack of radiologist recognition is problematic.

DISCUSSION & CONCLUSION

DLMs are common. The LM clinically functions as an organ with critical CNS-sustaining roles involving the SAS-pia structure, enclosed cells, lymphatics, and biologic pathways. Cases involve all specialties. Causes are numerous, symptoms predictable, and outcomes dependent on time to treatment and extent of residual SAS damage. An international disease classification and possible treatment trials are proposed.

Caspase-3 and -7 mediate apoptosis of human Chang's conjunctival cells induced by enterovirus 70

Enterovirus 70 (EV70) is the major etiological agent of acute hemorrhagic conjunctivitis (AHC). EV70 m.o.i.- (multiplicity of infection) and time-dependently induced apoptosis in human Chang's conjunctival (HCC) cells. UV- or heat-inactivated EV70 did not induce apoptosis. EV70-induced apoptosis was inhibited by cycloheximide and methoxysuccinyl-Ala-Ala-Pro-Val-chloromethylketone (MPCMK), but not actinomycin D and guanidine.HCl (although guanidine.HCl inhibited the apoptosis induced by EV70 infection at 0.5 PFU/cell for 18 h). EV70 infection induced activation of caspase-3 and -7 and degradation of the constitutively activated caspase-6. EV70-induced apoptotic DNA ladders and activated caspase-3 and -7, correlated with virus release. Caspase inhibitor IX (Z-VD-FMK) inhibited EV70-induced apoptosis and virus release, but not intracellular viral production. The results suggest that infectious virus and the syntheses of viral proteins especially EV70 proteases, but not viral genome RNA, are required for caspase-3 and -7-mediated EV70-induced apoptosis, and that apoptosis through cell lysis promotes EV70 release from HCC cells.

Neurological complications of acute haemorrhagic conjunctivitis

Forty four cases of the neurological complications of acute haemorrhagic conjunctivitis (AHC) seen in India during 1981 epidemic are reported. The disease predominantly affected adult males. The preceding attack of AHC, a latent period, prodromal symptoms of fever, myalgia and root pains followed by acute onset of lower motor neurone paralysis of limbs and/or cranial nerves formed the classical picture of neurological involvement. The recovery was poor and nearly half of the patients remained severely handicapped. Electrophysiological studies showed early appearance of widespread fibrillations and fasciculations, large polyphasic potentials of increased amplitude and reduced interference pattern. Nerve conduction studies were normal in most of the cases. Cerebrospinal fluid (CSF) examination revealed lymphocytic pleocytosis and rise in protein content. Significant antibody titres against enterovirus type 70 (EV 70) were demonstrated in the serum and the CSF. HLA studies showed low occurrence of A2 and B15 HLA antigens. Muscle biopsies revealed neurogenic atrophy and sural nerve biopsies were histologically unremarkable. The similarities of this disease with poliomyelitis and its pathogenesis are discussed.

A study of the neurological disorder associated with acute haemorrhagic conjunctivitis due to enterovirus 70

Ninety cases of the neurological manifestations associated with acute haemorrhagic conjunctivitis caused by Enterovirus 70 (EV 70) are reported. The patients were seen during the widespread epidemics in 1971 and 1981. Male adults were predominantly affected by a "polio-like" paralysis of the limbs and/or cranial nerves. Root pains were often complained of early in the disease. In the absence of a necropsy, clinical and neurophysiological examinations helped to localise the lesions. Significant antibody titres against EV 70 were demonstrated in the serum and more relevantly in the CSF. Though other viruses can cause sporadic and epidemic conjunctivitis and similar paralysis independently, the combination of a haemorrhagic conjunctivitis and a neurological disease mostly simulating poliomyelitis is caused by EV 70 alone. It is therefore suggested that this combination be called "Enterovirus 70 disease". Because of its neurovirulence, it is important to identify this virus at the very beginning of an epidemic of conjunctivitis, so as to limit its spread by strict public health measures.

Adult polio-like syndrome following Enterovirus 70 conjunctivitis (natural history of the disease)

During the Indian EV 70 conjunctivitis epidemic in 1981, 79 patients with neurological complications were evaluated by clinical, electrophysiological, histopathological and virological studies. The disease was heralded by an attack of conjunctivitis and was followed, after a variable latent period, by a pre-paralytic, paralytic, and post-paralytic stage of slow recovery. The above events occurred in an orderly sequence. The paralysis affected the cranial nerves, limbs or both. The clinical course closely simulated poliomyelitis, without any evidence of radiculopathy or myelopathy. Cranial nerve palsies were seen in approximately half of the patients. The electrophysiological and histologicl studies pointed towards the affection of anterior horn cells. The raised neutralizing antibody titres to Enterovirus 70, confirmed the aetiology of the disease. On the available data, we believe that this nosological entity should be considered under the general title of "polio-like syndrome" following EV 70 conjunctivitis. On account of two epidemics in 1971 and 1981 with unfavourable prognosis and high resultant disability, and because of lack of specific therapy, it has become imperative to develop, as a top priority, a vaccine for immunization.