1. Introduction
Delirium of cutaneous and parasitic infestation, or Ekbom syndrome, is a rare condition characterised by the unshakeable belief that small animals (insects, maggots, vermin) are crawling under the skin. It is more often observed by dermatologists than psychiatrists (Bourgeois, 2011) . It is a chronic disorder that can appear at any age, but more frequently in elderly patients and predominantly in women (Berhili et al., 2016) . This monothematic delirium, underpinned by tactile or visual hallucinations, is generally accompanied by significant anxiety (Bourgeois, 2011) . Psychiatric consultations are often sought at a later stage, via general medicine and then dermatology. Although common in Africa, Ekbom syndrome is rarely reported in sub-Saharan Africa. There is no clinical description of this condition in the Togolese context. We therefore report this case from Togo.
2. Case Presentation
The patient in question was Mrs Y., a 79-year-old retired teacher who had been widowed 26 years previously. She was brought in by her daughter at the latter’s request, following a complaint of insects crawling out of her body and pruritus that had been going on for six years. The accompanying daughter was HIV-infected and under psychiatric care for somatisation. It was during the course of her treatment that, faced with the mention of her mother’s state of health, we decided to take her to a psychiatric consultation. Mrs Y. lives with one of her daughters, who doesn’t have the time to look after her. She consulted a dermatologist three years ago for itchy lesions on her back. These signs were accompanied by headaches, insomnia on waking, hypersialorrhoea and weight loss.
Her history of hypertension included treatment with Captopril and Atenolol with good compliance. There was no evidence of sensory-motor deficits. The interview did not reveal any psychiatric history or use of psychoactive substances. There was a family history of migraine. It should be noted that Mrs Y. is very sensitive to life events and likes to be surrounded.
The physical examination revealed numerous scratching lesions, particularly on the upper limbs and back. The hypersalivation was explained by the patient as a way of removing insects from her mouth. Osteotendinous reflexes were slightly sharp, with no other signs of extrapyramidal syndrome. There was no general sensitivity disorder either. Examination of the other systems, particularly the cardiac, skin and skin Appendages, pulmonary and osteoarticular systems, was unremarkable.
The psychiatric examination revealed a normal presentation with syntone contact. She expressed her suffering from this long illness, despite the dermatological treatments she had received. She had morning insomnia, anorexia, and visual and tactile hallucinations (she said she could see and feel insects biting her). She was anxious and had a definite anxiety-depressive state according to the HAD scale (A = 17; D = 15) (Hamilton, 1960; Aït-Ameur et al., 2000) . The patient had no sphincter disorders, no notion of running away or wandering, no mental automatism, no ideas of persecution, and no frank memory problems.
The standard laboratory work-up was carried out with no abnormalities found. Parasitological examination of the stools revealed no parasites. Parasitological examination of the skin was not available in our context and could not be carried out. Magnetic resonance imaging (MRI) revealed Fazekas stage III leukoaraiosis associated with a subtentorial multilacunar syndrome, moderate diffuse cortico-subcortical cerebral atrophy and a normal posterior fossa. We requested a neurological opinion for these MRI results and a cardiac opinion for his hypertension, both of which were unremarkable.
In view of this clinical picture and in the absence of any organic cause that could explain the symptoms, we made the diagnosis of Ekbom syndrome against a background of elderly depression. A drug treatment based on an antidepressant (Escitalopram 20 mg, one tablet in the morning) and an antipsychotic (Olanzapine 10 mg, one tablet in the evening) was instituted. Psychotherapy sessions to support the patient and psycho-educate her family and friends were provided during regular follow-up. After two months, the symptoms had regressed. The patient seen six months later had no further complaints.
3. Discussion
Delirium due to parasitic infestation is a rare chronic systematized monothematic delirium that can appear at any age but most often quite late in life (Ekbom, 2003) . Before the age of 50, Ekbom’s syndrome is as common in men as in women, but it is twice as common in women after the age of 60. The menopause favours xerosis of the skin at this age, which can aggravate the sensation of pruritus. Ekbom syndrome is also more common in subjects (especially females) who are emotionally isolated, generally live alone, have unstable moods and personality abnormalities of the sensitive type (vulnerability, distrust, psychorigidity) (Young, 2017; Ouédraogo et al., 2019) . This was the case with Mrs Y., a widow living with her daughter, who only shared a few minutes of quality time with the patient. The other children were in more telephone than physical contact with her, although they lived in the same town. The patient complained of loneliness.
The age of onset was generally advanced (64 years on average) and the average time to first contact with a psychiatrist was three years (Bourgeois, 2011) . Mrs Y. was 79 years old and consulted a psychiatrist around six years after the onset of symptoms. In their study, Ouédraogo et al. (Ouédraogo et al., 2019) described an 80-year-old patient who consulted two years after the onset of symptoms.
Ekbom syndrome may be primary or secondary to somatic pathologies (actual parasitosis, vitamin B12, folate and iron deficiency, cerebral disease, etc.).
Mrs Y’s history, examination and various investigations did not suggest an organic origin for the syndrome. We therefore concluded that it was a primary Ekbom syndrome.
Some people liken Ekbom syndrome to chronic hallucinatory psychosis (CHP), emphasising the context of social isolation in which these two illnesses develop and the existence of a rich psychosensory hallucinatory experience (Moroge et al., 2013) . Ekbom syndrome is considered by other authors to be a particular form of PHC. However, even if it has aspects in common with this pathology, it seems to constitute a nosographic entity in its own right (Bourée et al., 2007) . According to Gardella (Gardella, 2018) , the main underlying mechanisms of CHP are psychic hallucinations as well as grand mental automatism. On this basis, we can rule out the diagnosis of CHP in our patient due to the absence of mental automatism, ideas of persecution, and psychic hallucinations.
The diagnosis of elderly depression and even vascular dementia were also discussed by the team. In fact, Mrs Y, an elderly “African”, mother of children, widow and former teacher, should enjoy a special social status, being well cared for and receiving a great deal of attention. However, the reality was quite different and Mrs Y complained of loneliness. Her complaints were mainly sensations of insects crawling out of her body, leading to pruritus, hypersialorrhoea, insomnia and headaches. These somatic complaints were at the forefront, explaining the long delay of six years before her first psychiatric consultation. There were no thoughts of guilt or suicide.
In Africa, Gueye noted that “the frequency of somatic complaints, the rarity of ideas of guilt and suicidal ideation” should suggest depression in the elderly (Gueye et al., 1995; Karfo et al., 2007) .
Among the antidepressants that are best tolerated and associated with a lower risk of drug interactions, selective serotonin reuptake inhibitors (SSRIs) are recommended as first-line treatment for the elderly (sertraline, citalopram, escitalopram) (Cipriani et al., 2018; Patel et al., 2017; Taylor, 2014) .
Antipsychotics are among the types of medication most often implicated in metabolic disorders. Those recommended for the elderly are Risperidone and Olanzapine (Bourla & Ferreri, 2022) . We chose Escitalopram and Olanzapine for our patient’s treatment. These two drugs were available and accessible at the time of our patient’s treatment, which was the reason for their choice. Psychotropic drugs are not always available in pharmacies because of the many delays in their delivery to Togo. Also, most of the drugs available and recommended as first-line treatment are difficult for patients to afford, as insurance companies do not cover them. Mrs Y. was able to pay for her prescriptions thanks to her children. This is not often the case for the majority of Togolese.
Managing Ekbom syndrome is usually a difficult task. Patients generally find it very difficult to accept the “psychiatrisation” of their symptoms, and quickly fall into a frenzied, costly and prolonged quest for treatment (Bak et al., 2008; Berhili et al., 2016) . The relay between the dermatologist (or other specialists) and the psychiatrist is often poorly accepted by patients, and the frustration caused by the failure to respond to their request for treatment can lead to dangerous behaviour on their part or on the part of those around them. But multidisciplinary treatment (dermatologists, psychiatrists and psychologists) and a combination of antipsychotics and antidepressants can lead to a very favourable outcome.
4. Conclusion
Delirium of cutaneous and parasitic infestation is a rare and ubiquitous disease. It has been described since 1938 and was called “delire dermatozooique pre-senile” (Ekbom, 1938) . It occurs in sub-Saharan Africa but is poorly documented. Mrs Y. in Togo is a typical case reported. Treatment combining psychotropic drugs and psychotherapy resulted in a very favourable outcome.