The physical presentation of children infected with BPF include purpuric skin lesions affecting mainly the face and extremities, cyanosis, rapid necrosis of soft tissue, particularly the hands, feet, nose, and ears. Analysis of the fatalities due to BPF showed hemorrhage in the skin, lungs, and adrenal glands. Histopathology showed hemorrhage, intravascular microthrombi and necrosis in the upper dermis, renal glomeruli, lungs, and hepatic sinusoids. Risk factors
The risk factors associated with BPF are not well known. However, it has been suggested that children under 5 years of age are more susceptible to BPF since they lack serum bactericidal activity against the infection. Older children and adults have much higher titers of bactericidal antibodies, which serve as a protective measure. Also children residing in warmer geographic areas have been associated with a higher risk of BPF infection. Transmission
The eye gnat (Liohippelates) was thought to be the cause of the conjunctivitis epidemic which occurred in Mato Grosso do Sul in 1991. These gnats were extracted from the conjunctival secretions of the children who were infected with conjunctivitis. 19 of those children developed BPF following the conjunctivitis. Other modes of transmission include contact with the conjunctival discharges of infected people, ophthalmic instruments which have not been properly sterilized, sharing eye makeup applicators or multiple-dose eye medications. Pathogenesis
The pathogenesis of BPF is not well established but it is thought that patients become pharyngeal or conjunctival carriers of H. aegyptius, which is followed by spreading to the bloodstream.
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