Although infection is usually asymptomatic, patients infected with linguatulosis can present with discomfort and a prickling sensation in the throat extending to the ears and nasal passages, which can occur as soon as thirty minutes after eating infected meat (Cheng, 1986). These symptoms can progress to frontal headache, Eustachian tube congestion, abscess in the auditory canal, facial swelling, and abdominal pain, with clinical signs such as mesenteric lymph node inflammation, jaundice, dyspnea, dysphagia, coughing, sneezing, yellow nasal discharge, and in rare cases ocular lesions (Cheng, 1986; Siavashi et al., 2002; John and Petri, 2006).
Although ocular linguatulosis is extremely rare, one documented case presented with ocular pain, conjunctivitis, and visual difficulties due to shadowing (Lazo et al., 1999).
Linguatulosis often goes undetected, but can diagnosed by mechanically abstracting and microscopically identifying linguatulids from the larynx, nose, and gums, or linguatulid eggs from nasal mucus. Linguatula serrata nymphs are commonly identified by their rows of spines (Figure 3), and anterior extremity (Figure 4) bearing four hooks and a mouth (Siavashi et al., 2002; Mehlhorn, 2004). Nymphs migrate to the liver, spleen, lungs, and mesenteries where they encyst and calcify making them visible on chest or abdominal radiographs (Cheng, 1986; John and Petri, 2006).
Halzoun, Marrara syndrome, nasopharyngeal pentastomiosis, and visceral pentastomiosis presentations and diagnostic tests are similar to those mentioned above for linguatulosis.