Delusional parasitosis and the dopamine transporter. A new insight of etiology?

Skin Deep: An Overlap of Delusions

Delusional infestation (DI) describes a fixed, false belief where a person believes that they are infested with living or inanimate pathogens despite the absence of medical evidence for such infestation. Descriptions of alleged pathogens have evolved over time, incorporating inanimate objects such as fibrous strands. With the emergence of Morgellons disease and its controversy, we report a case of a 40-year-old female presenting with a strong belief of scabies infestation along with fibers emerging from her skin. Further, although insects are still the most alleged source of infestation, the overlap of Morgellons disease and the delusion of infestation supports it as a DI variant and questions the notion of its existence as a separate diagnostic entity.

Delusional Parasitosis Without Cutaneous Presentation: "I Have Moths in My Belly"

Delusional parasitosis is a psychiatric illness characterized by a false belief of a parasite infestation, despite evidence to the contrary. The disorder typically presents as a dermatologic condition since patients often itch and pick at their skin to relieve the perceived infestation. Patients often have numerous cutaneous lesions that never heal due to persistent picking. Another hallmark presentation known as the "matchbox sign" has patients collecting "evidence" of their perceived infestation. This patient believed that he had "moths" infesting his stomach, creating "web-like" structures that spread as far as his nostrils. In this case study, we describe this presentation of the disorder and contextualize our patient in the current literature on delusional parasitosis.

Psychological interventions in the treatment of delusional parasitosis: a brief review

This review synthesized evidence on the most up-to-date treatment outcomes in patients with delusional parasitosis and examined the impact of incorporating psychological interventions in conjunction with psychiatric treatment. The reporting of this review followed the Preferred Reporting Items for Systematic Reviews and Meta-Analysis guidelines. PubMed and Google Scholar were searched between 2013 and 2023. Nine studies were included in this review. Partial remission was observed across all cases, irrespective of the treatment approach employed. Complete remission was limited to only three studies. No correlation was observed between the incorporation of psychological intervention in conjunction with psychotropic medication and an enhanced remission outcome. The findings underscore the importance of psychotropic medication as a fundamental component in the treatment of delusional parasitosis. The results highlight that although first- and second-generation psychotropic medications are the mainstay treatment options, they nevertheless play a limited role because of the patients' steadfast delusions of infestations.

Insights into the Medical Evaluation of Ekbom Syndrome: An Overview

Ekbom syndrome, also known as delusional parasitosis (DP) or delusional infestation, is an uncommon psychiatric disorder distinguished by an enduring conviction of parasitic infestation, persisting notwithstanding the presence of medical evidence to the contrary. Primarily affecting middle-aged women, DP can manifest either as isolated psychological distress or as a component within a more intricate psychiatric framework, substantially influencing the quality of life for affected individuals. Its pathophysiological mechanism involves uncertain dopaminergic imbalances and dysfunction in the dopamine transporter system. Dermatologists often play a pivotal role in diagnosis, as patients first seek dermatological assessments of their signs and symptoms. However, DP frequently originates from underlying psychiatric disorders or medical variables, manifesting with neurological and infectious causative factors. The diagnostic complexity is attributed to patients' resolute convictions, leading to delayed psychiatric intervention. First-line DP treatment involves antipsychotics, with newer agents demonstrating promising prospects, but the lack of standardized protocols poses a significant therapeutic challenge. In this narrative review, both a comprehensive approach to this uncommon pathology and an update on the state of knowledge in this medical subfield focused on optimizing the management of DP are provided. The complexity of DP underlying its uncommon nature and the incomplete understanding of its pathophysiology highlight the need for further research through multicenter studies and multidisciplinary teams to enhance therapeutic efficacy and safety.

A Case Series of Delusional Infestation in Huntington's Disease

 Huntington's disease (HD) is an autosomal dominant disorder that affects the basal ganglia, caused by CAG repeats in the huntingtin gene. Delusional infestation (DI) is a rare psychotic manifestation of the disease. This report presents two cases of HD patients with DI, both middle-aged females. The first patient achieved remission of DI with olanzapine, later cross-tapered to risperidone, but had spontaneous relapses. The second experienced gradual resolution of DI with risperidone in the setting of iron repletion and amantadine discontinuation, although her other psychotic symptoms remained. These cases shed light on an uncommon condition and may help guide understanding of the most effective treatment for it.

Psychopathological symptoms in dermatology: A basic approach toward psychocutaneous disorders

Dermatological conditions impact not only an individual's physical body but also their psychological health. Similar to how cutaneous conditions can affect one's psychological health, worsening psychological conditions can exacerbate or even induce dermatological conditions. There are four common psychiatric pathologies typically found in dermatology practices: depressive symptoms, anxiety symptoms, obsessive-compulsive disorder behaviors, and psychosis. Common cutaneous disorders associated with these psychopathological symptoms include, but are not limited to, psoriasis, acne vulgaris, atopic dermatitis, urticaria, trichotillomania, excoriation disorder, and delusions of parasitosis. The goal of this review is to examine the relationship between these four psychopathological symptoms with common psychodermatological conditions and to help providers better diagnose and implement appropriate psychological support to treat their patients.

Seventy Years of Treating Delusional Disorder with Antipsychotics: A Historical Perspective

For many decades, delusional disorder (DD) has been considered a treatment-resistant disorder, with antipsychotics acknowledged as the best, though imperfect, treatment. It is possible that the discovery of the right drug could turn treatment resistance into treatment response. The goal of this narrative review is to provide a historical perspective of the treatment of DD since the introduction of antipsychotics 70 years ago. The following search terms were used to scan the literature: antipsychotics AND "delusional disorder". Findings were that therapy for DD symptoms has changed over time. Initial reports suggested that the drug of choice was the antipsychotic pimozide, and that this drug was especially effective for the somatic subtype of DD. Subsequent studies demonstrated that other antipsychotics, for instance, risperidone and olanzapine, were also highly effective. Treatment response may vary according to the presence or absence of specific symptoms, such as cognitive defect and depression. Clozapine, partial D2 agonists, and long-acting injectable drugs may be more effective than other drugs, but the evidence is not yet in. Because of the absence of robust evidence, treatment guidelines for the optimal management of DD are not yet available.

A Case of Delusional Parasitosis With Folie à Deux Treated With Low-Dose Quetiapine

A patient with a three-month history of persistent delusions of infestation presented to the emergency department with suicidal ideation secondary to complaints of worsening pruritus. Routine investigations failed to disclose any underlying organic cause for her pruritic sensations. The patient ascribed these to a parasitic infestation acquired following a brief stay at her maternal aunt’s residence. Following a thorough psychiatric assessment and collateral history obtained from her aunt, it became clear that both the patient and her aunt held similar delusions of infestation. Her aunt was found to be the main inducer. The patient was admitted, successfully treated with low-dose quetiapine, and eventually deemed fit for discharge. Delusional parasitosis and folie à deux are both rare conditions that may sometimes co-occur.

Case Report: Ekbom Syndrome Presented with Shared Psychotic Disorder

Background: Ekbom syndrome, which is also known as delusional parasitosis, is an infrequent psychotic disorder that is marked by a very intense and strongly unshakeable false belief that there is a parasitic infestation, usually occurring on or beneath the skin, even though there is no medical proof to explain it. This phenomenon can also present with a shared psychotic disorder which eventually is very rare, accounting for only 5-15%  of psychiatric cases worldwide.     Case Presentation: Mrs. Z, a 56-year-old woman, consulted the emergency unit of Universitas Sumatera Utara General Hospital along with her daughter, complaining of serious itchiness and skin problem due to crawling bugs and worms beneath her skin. Mrs. Z appeared furious, agitated and hyperventilating. Her daughter also admitted that she has the same skin condition. They have tried to appoint a consultation to several doctors but did not get any “appropriate” explanation. 1 ml of Haloperidol (5mg/ml) was initially administered via IM injection to calm Mrs. Z, and oxygen was given to help ease her breathing. We then advised Mrs.  Z and her daughter to visit our psychiatry outpatient clinic the day afteron the next day. Through a careful interview, we found that Mrs.  Z experienced Ekbom syndrome or delusional parasitosis that is also shared with her daughter. Both were given risperidone with an initial dose of 1 mg/day and sertraline 50mg/day.     Conclusion: We found a rare case of delusional parasitosis presented with shared psychotic disorder among a mother and a daughter. Initiation of psychiatric therapy is quite challenging, as patients often refuse due to stigmatization and their firm belief that instead of psychiatric illness, they actually have a parasitic infection. A multidisciplinary approach and strong patient-therapist relationship are a necessity in treating this type of patient.  

Treatments for Primary Delusional Infestation: Systematic Review

BACKGROUND

Delusional infestation, also known as Ekbom syndrome, is a rare delusional disorder characterized by the fixed belief that one is infested with parasites, worms, insects, or other organisms. Although delusional infestation is a psychiatric condition, patients often consult dermatologists with skin findings, and it is currently unclear what treatments are recommended for this disorder.

OBJECTIVE

We aimed to systematically review and describe the treatment and management of patients presenting with primary delusional infestation.

METHODS

A systematic search was conducted using Ovid on MEDLINE, Embase, PsycINFO, and the Cochrane Register of Clinical Trials. Relevant data, including treatment, dosage, response, adherence, and side effects, were extracted and analyzed.

RESULTS

A total of 15 case series were included, comprising 280 patients (mean age 53.3 years, 65.4% female) with delusional infestation. Overall, aripiprazole had the highest complete remission rate at 79% (11/14), although this was limited to 14 patients. Among drug classes, selective serotonin reuptake inhibitors were the most effective with a 79% (11/14) complete remission rate and 43% (9/21) partial remission rate in patients with comorbid depression, anxiety, or trichotillomania. First-generation antipsychotics and second-generation antipsychotics had similar complete remission rates (56/103, 54.4% vs 56/117, 47.9%, respectively) and partial remission rates (36/103, 35% vs 41/117, 35%, respectively).

CONCLUSIONS

Due to the rarity of delusional infestation, we only found 15 case series. However, we found that first-generation antipsychotics appear to be similar in effectiveness to second-generation antipsychotics for the treatment of primary delusional infestation. Larger studies and randomized controlled trials are needed to evaluate the efficacy of pharmacological therapy for delusional infestation.

TRIAL REGISTRATION

PROSPERO CRD42020198161; https://www.crd.york.ac.uk/prospero/display_record.php?RecordID=198161.

Drug-induced Delusional Infestation

It is considered that certain drugs might induce delusional infestation, yet, to date, no studies have been performed to identify the pharmacodynamics associated with these treatments. The aim of this review is to summarize current available knowledge of drug-induced delusional infestation. A literature search was performed for primary studies on suspected drugs reported to induce delusional infestation. Included articles were evaluated systematically using the Naranjo criteria. In addition, drug mechanisms of action were compared. The final selection included 31 studies, in which a total of 26 classes of drugs were identified. Anti-Parkinson drugs were most frequently associated with delusional infestation, followed by antidepressants, antiepileptics, antibiotics, prescription stimulants, and a few other drug groups. The current available literature suggests that the onset of delusional infestation is initiated by drug-induced alterations in neurotransmitter levels, predominantly dopamine, in the central nervous system.

Adverse psychocutaneous effects of prescription stimulant use and abuse: A systematic review

Although rare, psychocutaneous disorders induced by prescription stimulants have been reported throughout the literature. A systematic review was conducted to identify all case reports and case series of prescription stimulant-induced trichotillomania, tactile hallucinations, and delusional infestation. A total of 22 case reports were identified and relevant information was analyzed. Patients presenting with trichotillomania and tactile hallucinations induced by prescription stimulants were typically pediatric male patients being treated for attention deficit hypersensitivity disorder. Symptoms resolved after discontinuation of the offending medication. Patients presenting with delusional infestation secondary to stimulant use or abuse were typically adults who were misusing or abusing stimulant medication. Although symptoms typically improved or resolved after decreasing or discontinuing medication, several patients required the use of antipsychotic medication. While the observational nature of case reports and small number of patients limits meaningful analysis of trends and comparison, this study demonstrates that physicians, especially dermatologists and psychiatrists, should be aware of the potential for prescription stimulants to precipitate adverse psychocutaneous disorders in a minority of individuals.

Case report: Delusional infestation in dementia with Lewy bodies

BACKGROUND

Delusional infestation is characterized by delusions of being infested with parasites, vermin, or small insects and is frequently accompanied by tactile and visual hallucinations. Herein, we report two cases of dementia with Lewy bodies (DLB) with delusional infestation.

CASE PRESENTATION

Case 1 was an 83-year-old man. At the age of 75, he began to show symptoms of rapid eye movement sleep behavior disorder. At the age of 83, he began to complain of visual hallucinations of people and delusional infestation with tactile and visual hallucinations of insects, resulting in the use of insecticides for non-existent insects. He also complained of mild amnesia and was admitted to our psychiatric ward for evaluation and treatment. After admission, the delusional infestation disappeared without any new medication. Based on our examinations, he was diagnosed with probable DLB with delusional infestation. He was treated with 5 mg/day of donepezil hydrochloride; his visual and tactile hallucinations disappeared, and the delusional infestation had not recurred at the 1-year follow-up. Case 2 was a 69-year-old woman. At the age of 60, she underwent clipping for subarachnoid hemorrhage (SAH). At the age of 65, she began to have visual hallucinations of people. At the age of 67, she began to complain of visual illusions in which she mistook lint for insects. At the age of 69, she developed delusional infestation and mild amnesia. She took various actions to get rid of these non-existent insects, including insecticide use, consulting an exterminator, and visiting several dermatologists. She eventually burnt her leg in an attempt to kill the non-existent insects. Based on our examinations, she was diagnosed with prodromal DLB in addition to SAH sequelae. We determined that her delusional infestation was caused by DLB rather than SAH sequelae based on the course of her symptoms. She was treated with a combination of 3 mg/day of donepezil hydrochloride and 12.5 mg/day of quetiapine. Thereafter, the delusional infestation partially improved, and she took no further action against non-existent insects.

CONCLUSION

Delusional infestation may be caused by DLB. Acetylcholinesterase inhibitors (AChEI) may be effective for delusional infestation in DLB, although antipsychotics may also be needed in severe cases.

Right frontal meningioma presenting as delusional parasitosis

Central nervous system tumours can occasionally present with psychiatric symptoms as the only manifestation and can often pose diagnostic challenges. A man in his early 60s presented to the psychiatry outpatient department with delusional parasitosis. His old age and an episode of urinary and faecal incontinence made the clinician consider neuroimaging at the very first visit itself. He was detected to have a right frontal meningioma with features of intracranial hypertension with midline shift, and he underwent emergency surgery. His delusional symptoms completely resolved after surgery and did not recur during the follow-up period of 2.5 years. A right frontal meningioma presenting as delusional parasitosis has probably not been reported in the literature before, and the case is being reported to highlight the rarity of its presentation, the importance of eliciting a detailed clinical history and the need for early neuroimaging in these cases.

Dopamine, Serotonin, and Structure/Function Brain Defects as Biological Bases for Treatment Response in Delusional Disorder: A Systematic Review of Cases and Cohort Studies

Although blockade of dopamine receptors D2 and D3 appears to be the main mechanism of antipsychotic action, treatment response variability calls for an examination of other biological systems. Our aim is to systematically review reports of treatment response in delusional disorder (DD) in order to help determine its biological bases. Computerized searches of ClinicalTrials.gov, PubMed, and Scopus databases (from 1999 to September 2021) were systematically reviewed, in keeping with PRISMA directives. We used the search terms: (treat * OR therap * AND (delusional disorder)). We included all studies that explored the biological mechanisms of treatment response in DD, as diagnosed by ICD or DSM criteria. A total of 4344 records were initially retrieved, from which 14 papers were included: case reports, case series, and cohort studies. Findings point to (1) dopaminergic dysfunction (based on biochemical and genetic studies), (2) serotonergic dysfunction (based on partial agonism/antagonism of drugs), and (3) brain structure/function impairment, especially in the temporal and parietal lobes, as crucial factors in treatment response. Further studies with higher levels of evidence are needed to help clinicians determine treatment.

Delusional infestation: Clinical presentations, diagnosis, and management

BACKGROUND

Delusional infestation is a primary psychiatric disorder characterized by a somatic-type delusional disorder (primary delusional infestation) that may lead to self-induced cutaneous lesions which are often difficult to recognize and treat properly. It may be also secondary to other psychiatric disorders, medical diseases, or substance abuse.

AIMS

This review will describe prevalence, common clinical features, different clinical presentations, differential diagnoses, and treatment recommendation. Special focus has been put on psychological aspects.

METHODS

We conducted a literature search on PubMed from January 2001 to June 2020 with the search terms of delusional parasitosis, delusional infestation, psychological, Reference lists of identified articles were examined for further relevant studies. The search was limited to English language articles. No specified quality criteria were used for study inclusion.

RESULTS

The clinical manifestations of delusional infestation are very important in the differential diagnosis and its psychological implications and management perspectives.

CONCLUSION

This article presents an update regarding the clinical aspects and treatment options of delusional infestation in order to provide an up-to-date review for dermatologists and general practitioners.

Substance use disorders and chronic itch

Chronic pruritus is one dermatologic manifestation of an underlying substance use disorder. Recent literature has uncovered similarities between the general neurologic mechanisms of addiction and chronic itch, largely involving activation of the dopaminergic reward circuits within the brain and imbalances between mu and kappa opioid receptor activation. It is likely that the use of specific drugs, like central nervous system stimulants and opioids, results in further activation and imbalances within these pathways, perpetuating both addiction and pruritus simultaneously. Opioid users often present to dermatology clinics with a generalized pruritus, whereas individuals using central nervous system stimulants like cocaine and methylenedioxymethamphetamine (MDMA), as well as legally prescribed drugs like treatments for attention deficit hyperactivity disorder, frequently complain of crawling, delusional infestation-like sensations underneath the skin. Because of these overlapping mechanisms and similar clinical presentations to many other chronically itchy conditions, it is necessary for dermatologists to consider and investigate an underlying substance use disorder to effectively treat these patients.

Coexistence of Primary and Secondary Delusional Parasitosis

Objective

Delusional parasitosis (DP) is a difficult-to-treat condition. It is prevalent in all cultures, societies, and countries. Previous case reports of DP have been published; however, the patient presented in this report is unique because of the co-occurrence of both primary and secondary types of DP. We aim to explore the two subtypes of DP.

Conclusions

We discuss DP from a nosological perspective and also highlight the various theories at play in the pathogenesis of primary and secondary DP. The different subtypes of DP should be taken into consideration as they also have a bearing on the management.

The Pharmacology of Visual Hallucinations in Synucleinopathies

Visual hallucinations (VH) are commonly found in the course of synucleinopathies like Parkinson's disease and dementia with Lewy bodies. The incidence of VH in these conditions is so high that the absence of VH in the course of the disease should raise questions about the diagnosis. VH may take the form of early and simple phenomena or appear with late and complex presentations that include hallucinatory production and delusions. VH are an unmet treatment need. The review analyzes the past and recent hypotheses that are related to the underlying mechanisms of VH and then discusses their pharmacological modulation. Recent models for VH have been centered on the role played by the decoupling of the default mode network (DMN) when is released from the control of the fronto-parietal and salience networks. According to the proposed model, the process results in the perception of priors that are stored in the unconscious memory and the uncontrolled emergence of intrinsic narrative produced by the DMN. This DMN activity is triggered by the altered functioning of the thalamus and involves the dysregulated activity of the brain neurotransmitters. Historically, dopamine has been indicated as a major driver for the production of VH in synucleinopathies. In that context, nigrostriatal dysfunctions have been associated with the VH onset. The efficacy of antipsychotic compounds in VH treatment has further supported the notion of major involvement of dopamine in the production of the hallucinatory phenomena. However, more recent studies and growing evidence are also pointing toward an important role played by serotonergic and cholinergic dysfunctions. In that respect, in vivo and post-mortem studies have now proved that serotonergic impairment is often an early event in synucleinopathies. The prominent cholinergic impairment in DLB is also well established. Finally, glutamatergic and gamma aminobutyric acid (GABA)ergic modulations and changes in the overall balance between excitatory and inhibitory signaling are also contributing factors. The review provides an extensive overview of the pharmacology of VH and offers an up to date analysis of treatment options.

Delusions of Parasitosis: An Update

Delusional parasitosis, also known as delusional infestation or Ekbom syndrome, is a relatively infrequent psychotic disorder characterized by an unwavering false belief that there is a parasitic infestation of the skin, despite the absence of any medical evidence that could support this claim. Delusional parasitosis can be categorized into primary, secondary, and organic forms. Sometimes, close relatives also experience identical delusions. This phenomenon was reported to occur in 5-15% of cases, and is known as shared psychotic disorder-delusional parasitosis with folie à deux. Patients with delusional parasitosis frequently seek help from many physicians. Close multidisciplinary cooperation between clinicians is often key to shortening the time taken to diagnose this disorder. Initiation of psychopharmacological therapy is a challenge, as many patients refuse any psychiatric treatment because of the stigma associated with mental illness and because of their firm belief that they have a parasitic infestation, not a psychiatric condition. For many patients, a sense of a lack of understanding leads to isolation and the development of depression symptoms, which is why it is crucial to earn the trust of such patients while taking care of them.

Delusional parasitosis as presenting symptom of occipital lobe cerebrovascular accident

Delusional parasitosis manifests as a fixed, false belief that an individual is infested by living organisms. Primary delusional parasitosis is a psychiatric disorder with the delusion as an isolated manifestation, whereas secondary delusional parasitosis is a delusion occurring secondary to a psychiatric disorder, substance use, or medical illness. A 62-year-old woman with no psychiatric history presented to the Emergency Department with two to three months of "whole body itching" and seeing small insects crawling on her skin and in her hair. Exam of her skin and scalp was notable for no appreciable lesions, rashes, excoriations, or insects. Her neurologic exam was notable for full visual fields, and no localizing deficits. A non-contrast head CT demonstrated a nonspecific heterogeneous low-attenuation lesion within the medial right occipital lobe, and a follow up MRI confirmed a right posterior cerebral artery distribution subacute infarction. She was admitted for two days, and ultimately was discharged on aspirin and atorvastatin for secondary prevention. An emergency physician should remain vigilant in his/her assessment of patients with seemingly psychiatric symptoms, in particular elderly patients with no known psychiatric illnesses. Neuroimaging should be amongst studies considered in the evaluation of elderly patients presenting with new onset psychiatric complaints.

Delusional infestation in the treatment of ADHD with atomoxetine

The case describes an adult diagnosed with attention deficit hyperactivity disorder and treated with atomoxetine who quickly developed a florid case of delusional infestation. The patient described very distressing experiences that were significantly impacting her daily life. The symptoms improved with the withdrawal of atomoxetine and resolved completely with antipsychotic medications. Atomoxetine is proposed as the putative causative agent in this case.

Refractory Delusional Parasitosis in a 70-year-old Woman

This is a case report of delusional parasitosis in a 70-year-old woman. Delusional parasitosis, or delusional infestation, is a rare disorder typified by the false belief that an individual is infected with insects or parasites. Management focuses on developing a strong, caring relationship with the patient. It is widely debated whether health care providers should agree or disagree with the patient’s delusions. Due to the rarity of this disorder, our hope in presenting this incidence is to motivate more research for treatment. 

Regional gray matter volume and structural network strength in somatic vs. non-somatic delusional disorders

BACKGROUND

Monothematic delusional disorders are characterized by a single tenacious belief. They provide a great opportunity to study underlying brain structures in the absence of confounding symptoms that accompany delusions in schizophrenia. Delusional beliefs include persecution, jealousy or somatic delusions including infestation. It is unclear whether specific delusional content is associated with distinct neural substrates.

METHODS

We used magnetic resonance imaging in patients presenting with somatic vs. non-somatic delusional disorders. Patients with delusional infestation (DI, n=18), and individuals with non-somatic delusional disorders (n=19) were included, together with healthy volunteers (n=20). Uni- and multivariate techniques for structural data analysis were applied to provide a comprehensive characterization of abnormal brain volume at both the regional and neural network level.

RESULTS

Patients with DI showed lower gray matter volume in thalamic, striatal (putamen), insular and medial prefrontal brain regions in contrast to non-somatic delusional disorders and healthy controls. Importantly, these differences were consistently detected at regional and network level. Compared to healthy controls, patients with delusional disorders other than DI showed lower gray matter volume in temporal cortical regions.

CONCLUSION

The data support the notion that dysfunctional somatosensory and peripersonal networks could mediate somatic delusions in patients with DI in contrast to delusional disorders without somatic content. The data also suggest putative content-specific neural signatures in delusional disorders and in delusion formation per se.

Anti-N-methyl-D-aspartate receptor encephalitis associated with acute Toxoplasma gondii infection: A case report

RATIONALE

Anti-N-methyl-D-aspartate receptor (NMDAR) encephalitis has been recognized as the most frequent autoimmune encephalitis in children. Several infectious agents have been implicated in anti-NMDA encephalitis.

PATIENT CONCERNS

A previously healthy immunocompetent 9-year-old girl first presented with seizures, headaches and vomiting. Cerebrospinal fluid and brain magnetic resonance imaging were normal. After one week onset, the patient gradually developed unexplained personality and behavior changes, accompanied by fever and seizures again. Repeated CSF analysis revealed a slightly lymphocytic predominant pleocytosis and positive anti-NMDAR antibody. A variety of pathogenic examinations were negative, except for positive toxoplasma IgM and IgG.

DIAGNOSES

The patient was diagnoses for anti-NMDA encephalitis associated with acute acquired toxoplasma gondii infection.

INTERVENTIONS

The patient received 10 days azithromycin for treatment of acquired toxoplasma infection. The parents refuse immunotherapy because substantial recovery from clinical symptoms.

OUTCOMES

The patient was substantially recovered with residual mild agitation after therapy for acquired toxoplasma gondii infection. Two months later, the patient was completely devoid of symptoms, and the levels of serum IgM and IgG of toxoplasma gondii were decreased.

LESSONS

Acquired toxoplasma gondii infection may trigger anti-NMDAR encephalitis in children, which has not been reported previously. Clinicians should assess the possibility of toxoplasma gondii infection when evaluating a patient with anti-NMDA encephalitis.

Delusional Infestation in Parkinson's Disease

Delusional infestation (DI), a form of psychosis, has rarely been reported in patients with Parkinson disease (PD). The clinical presentation and successful treatment of DI is illustrated through 5 cases. Each patient developed DI during treatment for moderate to advanced Parkinson's disease, and only 2 had cognitive impairment. Two patients were on monotherapy: 1 on a dopamine agonist and the other on trihexyphenidyl. Three patients were receiving complex combination therapy with 2 to 5 different anti-Parkinsonian medications at the onset of their delusion. Selective discontinuation or reduction of these medications was key to the resolution of DI in each patient. Although the medication adjustments differed, the changes resulted in the reduction of anticholinergic effects or extracellular striatal dopamine levels. This series emphasizes the clinical features and management strategies for this disruptive form of psychosis in patients with PD.

Drug-Induced Tactile Hallucinations Beyond Recreational Drugs

In monosymptomatic hypochondriacal psychosis (MHP), such as delusional infestation (DI), the patient has a fixed, false, encapsulated belief associated with tactile hallucinations (TH), most commonly formication, which is defined as cutaneous sensations of crawling, stinging, biting, etc., without evidence of infestation. Drug-induced TH should be considered in patients with suspected MHP. Although recreational drugs such as cocaine, amphetamines, and narcotics are well known to induce TH, many busy practicing dermatologists may not be familiar with other types of medications that can induce TH. A literature search for peer-reviewed articles was conducted in the PubMed, PsychInfo, Cochrane, and Embase databases. For each article, the medication(s) that induced TH was identified in a systematic way. The most commonly reported group of medications to induce TH was anti-Parkisonian agents, followed by antidepressants, prescription stimulants, antihypertensives (propranolol), and antiepileptics. In many cases, other types of hallucinations, such as visual and auditory, were present. Patients also commonly presented with psychiatric comorbidities. Although the conclusions that can be derived from this literature review are limited, it appears that certain medications that alter neurotransmitters, especially dopamine and, less convincingly, norepinephrine and serotonin, can be associated with TH. Drug-induced TH should also be considered in patients presenting with multiple types of hallucinations and patients with existing psychiatric comorbidity. Drug-induced TH, especially with an underlying psychiatric diagnosis that is separate from MHP, may be a more manageable disease entity compared with bona fide MHP.

Interaction of multiple gene variants and their effects on schizophrenia phenotypes

BACKGROUND

Schizophrenia is a clinically heterogeneous disorder and may be explained by its complex genetic architecture. Many schizophrenia susceptibility genes were identified but the picture remains unclear due to inconsistent or contradictory genetic association studies. This confusion may, in part, be because symptoms result from the combined interaction of many genes and these interacting genes are associated with specific sub-phenotypes of schizophrenia rather than schizophrenia as a whole. This study investigates the relationship between schizophrenia susceptibility genes and schizophrenia sub-phenotypes by identifying multiple gene variant interactions.

MATERIALS AND METHODS

Fifty SNPs from 21 genes were genotyped in 235 Australian participants with schizophrenia screened for various phenotypes. Schizophrenia participants were grouped into relevant phenotype clusters using cluster analysis and normalized phenotype cluster scores were calculated for each patient. The relationship between genotypes and normalized phenotype cluster scores were analyzed by linear regression analysis.

RESULTS

Three phenotype clusters were identified. There was some overlap in symptoms between phenotype clusters, particularly for depression. However, cluster 1 appears to be characterized by speech disorder and affective behavior symptoms, cluster 2 has predominantly hallucination symptoms and cluster 3 has mainly delusion symptoms. Interaction of five SNPs was found to have an effect on cluster 1 symptoms; ten SNPs on cluster 2 symptoms; and eight SNPs on cluster 3 symptoms.

CONCLUSION

The interaction of specific susceptibility genes is likely to lead to specific clinical sub-phenotypes of schizophrenia. Larger patient cohorts with more extensive clinical data will improve the detection of gene interactions and the resultant schizophrenia clinical phenotypes.

Delusional infestation: are you being bugged?

This case report documents a 58-year-old male who presented to the clinic with a 12-month history of a burrowing sensation in his eyelids that he attributed to a parasitic infestation. After being extensively investigated and reviewed by relevant specialties, no evidence of parasitic infestation was found. He was diagnosed with and treated for blepharitis. Psychiatric referral for presumed delusional infestation (DI) was recommended. Despite this, he remained insistent in his belief of infestation, and was inevitably lost to follow-up. DI, previously known as delusional parasitosis, is a rare delusional disorder where affected individuals have a fixed, false belief that they have a parasitic infestation. Diagnosis can be challenging. Practitioners need to evaluate between primary and secondary DI carefully, as management differs depending on the etiology. Despite this, patients diagnosed with primary DI tend to be resistant to psychiatric referral. This report aims to optimize management by giving the reader a guideline for appropriate investigations and advice on patient approach. It is important to recognize hallmark features of DI to minimize self-inflicted trauma and associated psychosocial consequences. Effective treatment for DI is available, and devastating consequences, including blindness, can be avoided.

Regulation of ethanol intake under chronic mild stress: roles of dopamine receptors and transporters

Studies have shown that exposure to chronic mild stress decreases ethanol intake and preference in dopamine D2 receptor wild-type mice (Drd2 (+/+)), while it increases intake in heterozygous (Drd2 (+/-)) and knockout (Drd2 (-/-)) mice. Dopaminergic neurotransmission in the basal forebrain plays a major role in the reinforcing actions of ethanol as well as in brain responses to stress. In order to identify neurochemical changes associated with the regulation of ethanol intake, we used in vitro receptor autoradiography to measure the levels and distribution of dopamine D1 and D2 receptors and dopamine transporters (DAT). Receptor levels were measured in the basal forebrain of Drd2 (+/+), Drd2 (+/-), and Drd2 (-/-) mice belonging to one of four groups: control (C), ethanol intake (E), chronic mild stress exposure (S), and ethanol intake under chronic mild stress (ES). D2 receptor levels were higher in the lateral and medial striatum of Drd2 (+/+) ES mice, compared with Drd2 (+/+) E mice. Ethanol intake in Drd2 (+/+) mice was negatively correlated with striatal D2 receptor levels. D2 receptor levels in Drd2(+/-) mice were the same among the four treatment groups. DAT levels were lower in Drd2(+/-) C and Drd2 (-/-) C mice, compared with Drd2 (+/+) C mice. Among Drd2(+/-) mice, S and ES groups had higher DAT levels compared with C and E groups in most regions examined. In Drd2(-/-) mice, ethanol intake was positively correlated with DAT levels in all regions studied. D1 receptor levels were lower in Drd2(+/-) and Drd2(-/-) mice, compared with Drd2(+/+), in all regions examined and remained unaffected by all treatments. The results suggest that in normal mice, ethanol intake is associated with D2 receptor-mediated neurotransmission, which exerts a protective effect against ethanol overconsumption under stress. In mice with low Drd2 expression, where DRD2 levels are not further modulated, ethanol intake is associated with DAT function which is upregulated under stress leading to ethanol overconsumption.

Ekbom syndrome occurring with multi infarct dementia

Ekbom Syndrome is characterized by delusion that small living being infests skin. The clinical profile of this disorder has shown it to be associated with organic conditions. Neuroimaging studies implicate putamen as the brain structure involved in the pathophysiology. These are also known as organic delusional disorder and provide an opportunity to study biological causation of delusional disorder. We report a patient presented with a complaint of insects crawling on her body for last two years. She collected the peeled skin in a jar and claimed that these are insects. CT scan (brain) revealed multiple infarcts involving basal ganglia. She responded to Risperidone 4 mg daily.

Abnormal gray and white matter volume in delusional infestation

Little is known about the neural basis of delusional infestation (DI), the delusional belief to be infested with pathogens. Case series and the response to anti-dopaminergic medication indicate disruptions in dopaminergic neurotransmission in the striatum (caudate, putamen), but did not allow for population-based inference. Here, we report the first whole-brain structural neuroimaging study to investigate gray and white matter abnormalities in DI compared to controls. In this study, we used structural magnetic resonance imaging and voxel-based morphometry to investigate gray and white matter volume in 16 DI patients and 16 matched healthy controls. Lower gray matter volume in DI patients compared to controls was found in left medial, lateral and right superior frontal cortices, left anterior cingulate cortex, bilateral insula, left thalamus, right striatal areas and in lateral and medial temporal cortical regions (p<0.05, cluster-corrected). Higher white matter volume in DI patients compared to controls was found in right middle cingulate, left frontal opercular and bilateral striatal regions (p<0.05, cluster-corrected). This study shows that structural changes in prefrontal, temporal, insular, cingulate and striatal brain regions are associated with DI, supporting a neurobiological model of disrupted prefrontal control over somato-sensory representations.

Successful ziprasidone monotherapy in a case of delusional parasitosis: a one-year followup

Delusional parasitosis is characterized by the false idea that own body is infested by invisible mites, insects, or other parasites. This case report describes a 24-year-old woman with delusional parasitosis who was treated with ziprasidone monotherapy (120 mg/day) with a complete remission of delusion and followed for one year without symptom recurrences. These findings, although preliminary, indicate that further investigation of ziprasidone monotherapy for the treatment of delusional parasitosis is warranted in further trials.

Delusional parasitosis with hyperthyroidism in an elderly woman: a case report

Introduction

Delusional parasitosis is a rare, monosymptomatic psychosis involving a delusion of being infested with parasites. It is commonly observed among female patients over the age of 50. It is classified as a ‘delusional disorder’ according to the 10^th revision of the International Classification of Diseases and as a ‘delusional disorder - somatic type’ according to the Diagnostic and Statistical Manual, Fourth Edition. Delusional parasitosis was reported to be associated with physical disorders such as hypoparathyroidism, Huntington’s chorea and Alzheimer’s disease, among others. Other than vitamin deficiencies however, a causal relationship has not to date been identified. We present this case due to the rarity of Turkish patients with this condition, its duration of follow-up, and its temporal pattern of symptoms paralleling thyroid function tests.

Case presentation

Our patient was a 70-year-old white Anatolian Turkish woman with primary school education who had been living alone for the past five years. She presented to our psychiatry department complaining of ‘feeling large worms moving in her body’. The complaints started after she was diagnosed with hyperthyroidism, increased when she did not use her thyroid medications and remitted when she was compliant with treatment. She was treated with pimozide 2mg/day for 20 months and followed-up without any antipsychotic treatment for an additional nine months. At her last examination, she was euthyroid, not receiving antipsychotics and was not having any delusions.

Conclusion

Although endocrine disorders, including hyperthyroidism, are listed among the etiological factors contributing to secondary delusional parasitosis, as far as we are aware this is the first case demonstrating a temporal pattern of thyroid hyperfunction and delusions through a protracted period of follow-up. It may be that the treatment of delusional parasitosis depends on clarifying the etiology and that atypical antipsychotics may help in the management of primary delusional parasitosis. Further studies on the relationship between thyroid hormones and dopaminergic neurotransmission may be warranted.

Brain perfusion asymmetry in patients with oral somatic delusions

Oral cenesthopathy is a somatic delusion or hallucination involving the oral area and is categorized as a delusional disorder, somatic type. The pathophysiology of this intractable condition remains obscure. In this study, we clarified the pathophysiology of oral cenesthopathy by evaluating regional brain perfusion. We performed single photon emission computed tomography (SPECT) using (99m)Tc-ethylcysteinate dimer in 16 subjects (cenesthopathy:control = 8:8). The SPECT images were visually assessed qualitatively, and quantitative analyses were also performed using a three-dimensional stereotactic region-of-interest template. The visual assessment revealed a right > left perfusion asymmetry in broad areas of the brain among the patients. The quantitative analysis confirmed that the regional cerebral blood flow values on the right side were significantly larger than those on the left side for most areas of the brain in the patients. A comparison of the R/(R + L) ratios in both groups confirmed the significant brain perfusion asymmetry between the two sides in the callosomarginal, precentral, and temporal regions in the patients. Qualitative evaluation of the SPECT images revealed right > left brain perfusion asymmetry in broad regions of the brain. Moreover, the quantitative analyses confirmed the perfusion asymmetry between the two sides in the frontal and temporal areas. Those may provide the key for elucidation of the pathophysiology of oral cenesthopathy.

Ziprasidone in the treatment of delusional parasitosis

Delusional parasitosis is characterized by a patient's fixed false belief of being infested with parasites or small creatures. The first-line treatment options are typical antipsychotics such as pimozide. However, the accompanying extrapyramidal side effects might limit their use. We report on a patient with a good response to pimozide combined with ziprasidone. Ziprasidone is an atypical antipsychotic drug with a lower risk of extrapyramidal symptoms; thus, it might be considered a good first or second treatment option for delusional parasitosis.

Delusional parasitosis: Worms of the mind

Delusional parasitosis is an uncommon psychotic illness. Patients often report to dermatologists and physicians for treatment and are brought to psychiatric attention only for associated psychological distress. One such case is discussed in this report.

Delusional infestation: treatment outcome with antipsychotics in 17 consecutive patients (using standardized reporting criteria)

OBJECTIVE

The multietiological nature of delusional infestation (DI) implies that therapy needs to be customized according to the various forms of DI (primary/secondary). Usually, treatment of DI is difficult to achieve in psychiatric settings because of the patients' nonpsychiatric concept of the illness.

METHODS

We analyzed the data of all consecutive DI patients seen in the Psychiatric Outpatient Department of the General Hospital Bruneck/Italy from 1998 to 2010, including structural brain imaging findings. Standardized reporting criteria are applied for the presentation of the cases in a naturalistic setting.

RESULTS

Our sample consisted of 17 patients. Notably, 15 out of these 17 patients (88%) could be engaged in an antipsychotic treatment trial. With different, mainly second-generation antipsychotics, all but one patient profited from antipsychotics, at least after substances were changed: 12 (71%) of the cases reached full remission, and another 2 (12%) had partial remission. The average duration of treatment was remarkably long: 3.8 years. Eight cases were classified as secondary to a brain disorder or medical condition, four cases were classified as secondary to psychiatric disorders and five cases fulfilled the criteria for primary DI (i.e., delusional disorder somatic type). All cases secondary to a brain disorder/medical condition showed macroscopic brain lesions mainly in the basal ganglia.

CONCLUSIONS

Our study confirmed previous experience that an excellent clinical outcome can be achieved in unselected patients with different DI forms provided that patients can be engaged in antipsychotic treatment. Although studies in DI are difficult to conduct, randomized controlled trials would be desirable to evaluate specific antipsychotic medication in DI in general and in the different forms of DI. More sophisticated investigations (single photon emission computed tomography and positron emission tomography) than structural brain imaging (magnetic resonance imaging and computed tomography) are needed to better elucidate underlying brain dysfunction in DI.

Toxoplasma gondii infection in humans in China

Toxoplasmosis is a zoonotic infection of humans and animals, caused by the opportunistic protozoan Toxoplasma gondii, a parasite belonging to the phylum Apicomplexa. Infection in pregnant women may lead to abortion, stillbirth or other serious consequences in newborns. Infection in immunocompromised patients can be fatal if not treated. On average, one third of people are chronically infected worldwide. Although very limited information from China has been published in the English journals, T. gondii infection is actually a significant human health problem in China. In the present article, we reviewed the clinical features, transmission, prevalence of T. gondii infection in humans in China, and summarized genetic characterizations of reported T. gondii isolates. Educating the public about the risks associated with unhealthy food and life style habits, tracking serological examinations to special populations, and measures to strengthen food and occupational safety are discussed.

Self inflicted corneal abrasions due to delusional parasitosis

The authors report a case of self inflicted bilateral corneal abrasions and skin damage due to ophthalmic and cutaneous delusional parasitosis. A male in his 50s presented with a 10 year history of believing that parasites were colonizing his skin and biting into his skin and eyes. The patient had received extensive medical evaluations that found no evidence that symptoms were due to a medical cause. He was persistent in his belief and had induced bilateral corneal abrasions and skin damage by using heat lamps and hair dryers in an attempt to disinfect his body. The patient was treated with olanzapine along with treatment for his skin and eyes. His delusional belief system persisted but no further damage to his eyes and skin was noted on initial follow-up.