Case 200. Tick bite (55 y-o F)
         
    A white tick (Ixodes ovatus) stuck on the eye lid, removed together with the skin tissue    
         
   
Key words : Ixodes ovatus, tick, hypostome, staphylococcal infection. Australian tick bite paralysis, Ixodes holocyclus
   
         
   
zoonosis
   
     
 
     
Ixodes ovatus often parasitizes the eye lid (gross findings). No pain or itchy sensation is associated.   The hypostome of the gnathosoma (jaw portion of the tick) is inserted into the dermis, with formation of cement-like material at the ulcer base. Inflammation has been provoked. In the gnathosoma, well-developed striated muscles are observed (HE).
     
 
     
Reference case 200A
The eye lid skin showing inflammatory ulceration after forced removal of Ixodes ovatus. After forced removal of the tick, ulceration with purulent exudation is formed. A remaining hypostome is embedded in the eosinophilic cement material at the ulcer base (HE).
  Reference case 200A
Secondary infection of the eye lid skin after forced removal of Ixodes ovatus. Around the cement material at the base of ulcer, secondary coccal infection is observed (HE, high power). The cement material is Luxol fast blue-positive.
     
 
     
Reference case 200A
Secondary infection of the eye lid skin after forced removal of Ixodes ovatus. The cocci around the cement material are Gram-positive. Secondary staphylococcal infection is indicated.
  Reference case 200B
Histology of a tick removed together with the skin tissue. The anterior part of the tick is shown (HE). In the gnathosoma, striated muscles and salivary gland are observed. The gut lumen is filled with sucked blood. The exoskeleton is birefringent and poorly stained.
     
 
     
Reference case 200C
Gross findings of a blood-sucking tick, Ixodes turdus, on the abdominal skin. After blood sucking, the tick becomes swollen and reddish-colored.
  Reference case 200D
Gross findings of Amblyomma testudinarium spontaneously detached from the perineal skin. Amblyomma testudinarium likes the external genitalia and perianal region to be stuck.
     
 
     
Reference case 200E
Australian tick bite paralysis caused by Ixodes holocyclus in a 35 y-o Japanese female. A tick was stuck on the scalp during a trip in Queensland State, Australia. Ixodes holocyclus is known to secrete strong paralytic neurotoxin termed holocyclotoxin.
  Reference case 200E
Australian tick bite paralysis caused by Ixodes holocyclus in a 35 y-o Japanese female. Two days after resection, erythematous edema around the bite and right facial palsy appeared. The patient completely recovered in one month.
     
   
     
Reference case 200E
Australian tick bite paralysis caused by Ixodes holocyclus in a 35 y-o Japanese female. Gross features of Ixodes holocyclus. Removal of the tick allegedly induces and accelerates the paralytic symptoms in 1-2 days.