Hookworms

Case history

A 23-year-old male presented to his GP surgery with a 2-week-old bite on his left foot after travelling in Sri Lanka. Initially, this was itchy and erythematous with a purulent discharge. He was treated with flucloxacillin for an infected insect bite. Two weeks later, the discharge and erythema had settled. However, a linear track line was visible under the skin, which had moved since first presentation. Cutaneous larva migrans, more commonly known as hookworm, was suspected.

A phone call with the Liverpool School of Tropical Medicine and a discussion of the clinical photograph confirmed this to be a case of cutaneous larva migrans and a course of Ivermectin 200 mcg/kg STAT was suggested by the tropical medicine consultant.

However, when an attempt was made to prescribe Ivermectin, the drug was flagged as a red prescription under the clinical commissioning group and local prescribing committee guidance, requiring the prescription to be signed by a consultant in tropical medicine. This suggested two options for the patient:

Self-refer to the Liverpool School of Tropical Medicine through their online self-referral system. This would likely involve travelling to Liverpool for assessment and to collect treatment.

The patient was safety-netted for worsening symptoms, which included nausea, vomiting, diarrhoea and muscle cramps. These would suggest that eggs had been deposited.

Discussion

Hookworms are ground-transmitted helminths commonly found in southern China, southeast Asia and Africa (Loukas et al., 2016). The first understanding of these helminths started from laboratory experiments in 1896, with the first experimental human infection being in 1901 (Chapman et al., 2021). Entrance to the host is either through ingestion or skin penetration (Loukas et al., 2016). Skin penetration can cause entrance into the blood stream, and cause travel to the heart and lungs. From the lungs, parasites can translocate through the alveoli, and ascend through the pharynx to enter the gastrointestinal tract through the oesophagus. Hookworms mature after approximately 4 to 6 weeks and are capable of reproduction within the gastrointestinal tract. Their eggs are passed in faeces and can cause further spread. The most common complication from infection is haemorrhage from anticoagulant and antithrombic secretion (Abuzeid et al., 2020). Diagnosis is mainly from clinical characteristics; however microscopic examination of eggs and parasites can be done for morphology (Sunderkötter et al., 2014).

This case demonstrates the possible difficulties in treatment; the medication required a consultant’s prescription. A major issue in this case, was the nearest specialist centre being over an hour away from our rural practice. Forcing patients to travel for diagnostic appointments for a condition already diagnosed by a remote specialist is a loss of time for both the patient and clinical staff. If liaising with remote consultants, a prescription at the time of consultation could prevent this issue.