Mycoplasmal cerebral vasculopathy in a lymphoma patient: Presumptive evidence of Mycoplasma pneumoniae microvascular endothelial cell invasion in a brain biopsy

Mycoplasmal panencephalitis: a neuropathologic documentation

“…In addition, perivascular immunoreactive macrophages might simply indicate the presence of microorganisms or their proteins in circulating monocytes that have crossed a compromised blood-brain-barrier. Recently, several patients were reported to have had a subacute to chronic motor and cognitive syndrome associated with a mycoplasmal infection of brain endothelial cells and consequent white matter lesions, in the absence of inflammatory cells or infection beyond brain endothelial cells [6,10,16,17]. We believe that our current report is the first unequivocal neuropathologic confirmation of direct infection or invasion of brain extravascular parenchymal cells by mycoplasma.…”

“…All reports document severe cerebral vasogenic edema and perivascular inflammation. Tissue neutrophils were prominent in the brain of two patients [4,13] and the CSF of one [2], moderate in one [10] and essentially absent in ours. Three cases do not fully support the PCR-derived hypothesis that early-onset encephalitis reflects direct infection by mycoplasma [2,4], but the other suggests this pathomechanism [13].…”

“…3b, c). They often contain an electron-dense ''nucleoid'', as reported in Mycoplasma hominis [1,5], in a previous study by one of us [16], and that of Rhodes et al [10]. They are also often associated with a rim of ribosomes and rarely display a connection between two, suggestive of budding (Fig.…”

“…The authors interpreted the latter finding as evidence of ''neuroinvasion'', which would confirm the hypothesis that direct infection may be the most probable pathomechanism for acute encephalitis in mycoplasmal infections. However, some may argue that true neuroinvasion necessitates the infection of brain parenchymal cells (i.e., brain vascular cells, neurons, astrocytes, microglia, or oligodendrocytes) [10]. In addition, perivascular immunoreactive macrophages might simply indicate the presence of microorganisms or their proteins in circulating monocytes that have crossed a compromised blood-brain-barrier.…”

Insights into the pathogenesis of Mycoplasma pneumoniae

“…In addition, during invasion, certain enzymes inside M. pneumoniae , including hydrolase, nuclease and phosphoprotein phosphatase shift to the host cells. Nuclease degrades DNA in host cells, whereas phosphoprotein phosphatase interferes with the activity of serine/threonine and tyrosine protein kinase (26,27). …”