Immunological disturbance and infectious disease in anorexia nervosa: a review

Unveiling the devastations of Streptococcus sanguinis infective endocarditis masquerading as iron deficiency anaemia: a case report

Background

Iron deficiency is the leading cause of anaemia worldwide and frequently observed in adolescent women, particularly those with eating disorders like anorexia nervosa. Consequently, clinicians may overlook iron deficiency anaemia, potentially missing a more serious diagnosis.

Case summary

A 19-year-old woman was referred to the hospital by her general practitioner due to worsening symptomatic iron deficiency anaemia, despite treatment with oral iron supplementation. Her blood cultures consistently grew Streptococcus sanguinis, and an echocardiogram revealed vegetations on the mitral and tricuspid valves, confirming the diagnosis of infective endocarditis. Several systemic complications of varying acuity were identified, including a ruptured left common iliac artery aneurysm with active haemorrhage into the left psoas muscle, enlarging cerebral, hepatic, and right common femoral artery aneurysms, splenic infarction with abscess formation, and an infected left psoas muscle haematoma. Multimodal imaging and collaboration within the multidisciplinary endocarditis team were crucial for coordinating further evaluation and managing the complex array of peripheral lesions in infective endocarditis. The patient was discharged with a good clinical outcome after 81 days.

Discussion

This case highlights the risks of overlooking iron deficiency anaemia in adolescent women with anorexia nervosa and the serious consequences of untreated complicated infective endocarditis. It emphasizes the need for thorough investigation of anorexia nervosa patients for infections due to their reduced clinical response, to ensure early diagnosis and treatment.

Diagnosis and clinical management of Exophiala dermatitidis pneumonia in a patient with anorexia nervosa: A case report

We report a patient with anorexia nervosa without bronchiectasis and cystic fibrosis who developed acute pneumonia caused by Exophiala dermatitidis (E. dermatitidis). The black fungus found in multiple sputum cultures was determined to be E. dermatitidis using mass spectrometry and identified using genetic analysis. Although the initiation of antifungal therapy was late, the pneumonia gradually improved with long-term treatment. This case highlights the need for early diagnosis and effective long-term treatment of the fungal etiologic agent.

Medical morbidity and risk of general hospital admission associated with concurrent anorexia nervosa and COVID-19: An observational study

OBJECTIVE

Investigate medical morbidity and risk of general hospital admission for patients with concurrent coronavirus disease 2019 (COVID-19) and anorexia nervosa (AN) who have not received severe acute respiratory syndrome coronavirus 2 vaccination.

METHODS

United Kingdom eating disorders clinicians contributed to a database of patients with an eating disorder and COVID-19. We used this to investigate demography, symptoms, hospitalization, treatment, and outcomes for those with AN.

RESULTS

We describe data for 49 patients (median age 21.5 years [interquartile range 17.0-33.5], 46 female) including 36 adults and 13 under-18-year-olds. Three (6.1% [95% confidence interval 1.3%-17.9]) were admitted to a general hospital. For this sample, the expected age-standardized hospital admission rate per COVID-19 case (based on the general population of England) was 2.6% and therefore not significantly different to the hospitalization rate we observed. Three (including two of those admitted to hospital) contracted pneumonia. One had severe pneumonia and was admitted to an intensive care unit. No deaths or use of mechanical ventilation were recorded.

DISCUSSION

To our knowledge, this represents the first study investigating medical morbidity or frequency of hospitalization for patients with COVID-19 and AN. We did not find evidence that patients with AN are at increased risk of severe COVID-19.

PUBLIC SIGNIFICANCE

Medical morbidity and risk of hospitalization associated with concurrent COVID-19 and anorexia nervosa (AN) had not, to our knowledge, been studied before. We used a database of patients with eating disorders and COVID-19 (to which United Kingdom clinicians had contributed) to investigate presentation, treatment, outcomes, and COVID-19 severity for those with AN and COVID-19. We did not find evidence that patients with AN are at increased risk of severe COVID-19.

Skin microbiota analysis in patients with anorexia nervosa and healthy-weight controls reveals microbial indicators of healthy weight and associations with the antimicrobial peptide psoriasin

Anorexia nervosa (AN), a psychiatric condition defined by low body weight for age and height, is associated with numerous dermatological conditions. Yet, clinical observations report that patients with AN do not suffer from infectious skin diseases like those associated with primary malnutrition. Cell-mediated immunity appears to be amplified in AN; however, this proinflammatory state does not sufficiently explain the lower incidence of infections. Antimicrobial peptides (AMPs) are important components of the innate immune system protecting from pathogens and shaping the microbiota. In Drosophila melanogaster starvation precedes increased AMP gene expression. Here, we analyzed skin microbiota in patients with AN and age-matched, healthy-weight controls and investigated the influence of weight gain on microbial community structure. We then correlated features of the skin microbial community with psoriasin and RNase 7, two highly abundant AMPs in human skin, to clarify whether an association between AMPs and skin microbiota exists and whether such a relationship might contribute to the resistance to cutaneous infections observed in AN. We find significant statistical correlations between Shannon diversity and the highly abundant skin AMP psoriasin and bacterial load, respectively. Moreover, we reveal psoriasin significantly associates with Abiotrophia, an indicator for the healthy-weight control group. Additionally, we observe a significant correlation between an individual's body mass index and Lactobacillus, a microbial indicator of health. Future investigation may help clarify physiological mechanisms that link nutritional intake with skin physiology.

Anorexia nervosa and COVID-19 infection: Clinical case report

The true risk of COVID-19 infection in anorexia nervosa (AN) including the duration of viral RNA shedding and infectivity is still unclear. We report on a case of a patient with severe AN with a mild course of COVID-19 and prolonged viral RNA shedding for at least 39 days after symptom onset. A careful evaluation of long-term infectivity must include viral load, live virus isolation, and viral genome sequencing.

Candida brain abscesses in a patient with anorexia nervosa receiving total parenteral nutrition

A 28-year-old woman with anorexia nervosa (AN) and Candida brain abscesses was transferred to our hospital for intensive treatment. On admission, she had a low-grade fever but no clinical neurological abnormalities were observed, even though she had a high-grade fever in the previous hospital. These clinical findings did not suggest a serious disorder in the brain. However, magnetic resonance imaging showed mass lesions in bilateral lentiform nuclei in addition to several abscesses in the whole body. The fungal cultures of specimens from abscesses on the anterior chest wall and iliopsoas muscle detected Candida albicans. She was treated with antifungal therapy (fosfluconazole, fluconazole, liposomal amphotericin B, and flucytosine) and two emergent craniotomies for drainage of the intracranial fluid. Thereafter, antifungal medications (voriconazole and flucytosine) were administered for six months as a longterm treatment, which abolished most abscesses. However, severe frontal lobe dysfunction persisted as a residual symptom. This case suggests that AN can mask clinical manifestations of infection. We should always consider the possibility of infectious complications in these patients.

The Role of the Gut Microbiome, Immunity, and Neuroinflammation in the Pathophysiology of Eating Disorders

There is a growing recognition that both the gut microbiome and the immune system are involved in a number of psychiatric illnesses, including eating disorders. This should come as no surprise, given the important roles of diet composition, eating patterns, and daily caloric intake in modulating both biological systems. Here, we review the evidence that alterations in the gut microbiome and immune system may serve not only to maintain and exacerbate dysregulated eating behavior, characterized by caloric restriction in anorexia nervosa and binge eating in bulimia nervosa and binge eating disorder, but may also serve as biomarkers of increased risk for developing an eating disorder. We focus on studies examining gut dysbiosis, peripheral inflammation, and neuroinflammation in each of these eating disorders, and explore the available data from preclinical rodent models of anorexia and binge-like eating that may be useful in providing a better understanding of the biological mechanisms underlying eating disorders. Such knowledge is critical to developing novel, highly effective treatments for these often intractable and unremitting eating disorders.

COVID-19, anorexia nervosa and obese patients with an eating disorder - some considerations for practitioners and researchers

Since COVID-19 is a global health emergency, there is an urgent need to share experiences on decision-making with regard to safety recommendations and for hypotheses that can inform a more focused prevention and treatment. Moreover, combining research into eating disorders and obesity with research into COVID-19 may provide a unique opportunity to shed light on the susceptibility to COVID-19.

Antimicrobial peptides in patients with anorexia nervosa: comparison with healthy controls and the impact of weight gain

Clinical observations show that patients with anorexia nervosa (AN) are surprisingly free from infectious diseases. There is evidence from studies in Drosophila melanogaster that starvation leads to an increased expression of antimicrobial peptides (AMPs). AMPs are part of the innate immune system and protect human surfaces from colonization with pathogenic bacteria, viruses and fungi. We compared the expression of AMPs between patients with AN and healthy controls (HC) and investigated the influence of weight gain. Using a standardized skin rinsing method, quantitative determination of the AMPs psoriasin and RNase 7 was carried out by ELISA. Even though non-significant, effect sizes revealed slightly higher AMP concentrations in HC. After a mean weight gain of 2.0 body mass index points, the concentration of psoriasin on the forehead of patients with AN increased significantly. We could not confirm our hypotheses of higher AMP concentrations in patients with AN that decrease after weight gain. On the contrary, weight gain seems to be associated with increasing AMP concentrations.

Severe bronchiectasis and inflammatory lung disease in a patient with anorexia nervosa and severe and enduring malnutrition - a case report

BACKGROUND

Persistent structural changes of the lungs in anorexia nervosa (AN) patients are rarely described in contemporary medical literature. The objective of our paper is to report a rare case of severe bronchiectasis and inflammatory changes to the lungs resulting from chronic malnutrition in a AN patient.

CASE PRESENTATION

We describe a patient with severe inflammatory lung disease caused by malnutrition, resulting in persistent bronchiectasis accompanying AN. We performed an analysis of the patient's medical records including radiological findings and laboratory results. A review of available literature shows very little data available on this topic.

CONCLUSION

Bronchiectasis and other structural changes of the lungs are rare, but severe complications of severe, chronic malnutrition. As exemplified by our case report, they may require extensive differential diagnosis and pose a significant clinical challenge due to their non-reversible character. A successful treatment relies heavily on the patient's compliance and may be hard to achieve. Clinicians managing patients with anorexia nervosa should be wary of early respiratory tract dysfunction-related symptoms and always consider malnutrition bronchiectasis as a differential diagnosis option.

Extremely severe anorexia nervosa: Hospital course of 354 adult patients in a clinical nutrition-eating disorders-unit

BACKGROUND AND AIMS

The clinical nutrition-eating disorders-unit in Raymond Poincaré Hospital is a reference center for the management of severe malnutrition and its complications in patients with anorexia nervosa (AN). The purpose of this study is to specify socio-demographic, anamnesic and clinical characteristics of AN patients hospitalized for extreme malnutrition, to identify types and prevalence of medical complications presented during their hospitalization for refeeding and the evolution of patients nutritional status.

METHODS

Demographic, clinical and paraclinical data of 354 severely malnourished AN patients were collected, during their first hospitalization in the unit, between November 1997 and January 2014, through medical records. The prevalence of medical complications was compared between the 2 AN subtypes (restricting and binging-purging).

RESULTS

339 patients were female and mean age was 28.7 ± 10.7 years old. Duration of AN was 9.5 ± 9 years, 173 (48.9%) patients had a restricting AN subtype. BMI at admission was 12.2 ± 1.6 kg/m², 280 (79.3%) patients had already been hospitalized for AN in other hospitals before. Psychiatric comorbidities were present in 168 (47.5%) patients. Associated somatic comorbidities concerned 70 (19.8%) patients. Outcomes during hospitalization were marked by 4.1 ± 3.9 kg weight gain on 36.9 ± 30.5 days. Enteral nutrition was provided in 304 (85.9%) patients. Main medical complications during hospitalization were: anemia (79%), neutropenia (53.9%), hypertransaminasemia (53.7%), osteoporosis (46.3%), hypokalemia (39.5%), hypophosphatemia (26%), hypoglycemia (13.8%), infectious complications (24.3%), cardiac dysfunction (7.1%), and proven gelatinous bone marrow transformation (6.5%). Hypokalemia was more frequent in binging-purging subtype. Lympho-neutropenia and hypertransaminasemia were more frequent in restricting subtype. During their hospitalization, 35 (10%) patients were referred to medical intensive care unit and 5 patients died.

CONCLUSIONS

AN patients hospitalized for severe malnutrition in a specialized clinical nutrition unit have severe and frequent medical complications. Psychiatric comorbidities are also frequent and could complicate medical care. A specialized and multidisciplinary management of these patients is therefore essential.

A systematic review of in vitro cytokine production in eating disorders

BACKGROUND

Eating disorders (EDs) have been associated with alterations in cytokine concentrations and production. This review examines whether in vitro cytokine production (i) is altered in people with EDs compared to healthy participants; and (ii) changes in response to treatment?

METHODS

Using PRISMA guidelines, we systematically reviewed articles reporting group comparisons or longitudinal assessments of spontaneous and/or stimulated cytokine production in vitro in people with EDs.

RESULTS

Twelve studies were included. Cross-sectional results were mixed in anorexia nervosa. Only one study measured cytokine production in bulimia nervosa. Two longitudinal studies showed that daily yoghurt consumption increases phytohemagglutinin-stimulated interferon-γ production in anorexia nervosa.

CONCLUSION

The mixed results could be accounted for by variations in experimental design. Our findings suggest that cytokine production could possibly be modulated through dietary interventions. However, due to the methodological heterogeneity and shortcomings of the included studies, it seems unreasonable to draw further conclusions.

Anorexia Nervosa and Autism Spectrum Disorders: Future Hopes Linked to Mucosal Immunity

Mental health is becoming a public health priority worldwide. Anorexia nervosa and autism spectrum disorders are 2 important types of childhood disorders with a bad prognosis. They share cognitive impairments and, in both cases, the microbiota appears to be a crucial factor. Alteration of the microbiota-gut-brain axis is an appealing hypothesis to define new pathophysiological mechanisms. Mucosal immunity plays a key role between the microbiota and the brain. The mucosal immune system receives and integrates messages from the intestinal microenvironment and the microbiota and then transmits the information to the nervous system. Abnormalities in this sensorial system may be involved in the natural history of mental diseases and might play a role in their maintenance. This review aims to highlight data about the relationship between intestinal mucosal immunity and these disorders. We show that shared cognitive impairments could be found in these 2 disorders, which both present dysbiosis. This literature review provides details on the immune status of anorexic and autistic patients, with a focus on intestinal mucosal factors. Finally, we suggest future research hypotheses that seem important for understanding the implication of the gut-brain-axis in psychiatric diseases.

A meta-analysis of cytokine concentrations in eating disorders

Cytokines are signalling molecules, which play an important role in both immune system function and brain development and function, and subsequently mental states and behaviour. Cytokines have been implicated in eating disorders (EDs) due to their role in psychological health, body weight and appetite regulation. This meta-analysis examined cross-sectional and longitudinal studies measuring concentrations of cytokines in individuals with EDs. Using PRISMA guidelines, we systematically reviewed relevant articles in PubMed, Web of Science, and MEDLINE. Random-effects meta-analyses were conducted for interleukin (IL)-1β, IL-6, transforming growth factor (TGF)-β, and tumor necrosis factor (TNF)-α, independently, firstly with all EDs combined and then stratified by ED diagnosis. Twenty-five studies were included: serum/plasma cytokine concentrations were measured in people with anorexia nervosa (AN) in 23 studies and bulimia nervosa (BN) in 4 studies. TNF-α and IL-6 were elevated in ED participants compared to healthy controls (HCs). Specifically, this pattern was seen only when comparing AN participants to HCs. Concentrations of these cytokines did not differ between people with BN and HCs. IL-1β and TGF-β did not differ between HCs and any ED group. Therefore, AN seems to be associated with elevated concentrations of TNF-α and IL-6. Considering the role of cytokines in appetite, mood regulation, and anxiety, these pro-inflammatory cytokines could be a potential future drug target to help people with AN, not only with weight gain, but also with various coexisting psychological problems. Future studies should consider confounding factors that affect cytokine concentrations and report ED-relevant clinical characteristics.

A child with anorexia nervosa presenting with severe infection with cytopenia and hemophagocytosis: a case report

Background

Patients with anorexia nervosa in the acute phase have physical complications, such as infectious disease. Although hemophagocytic syndrome due to infection is a rare complication in anorexia nervosa, early identification for hemophagocytosis is important for avoiding a life-threatening condition.

Case presentation

We report a case of a 12-year-old girl with anorexia nervosa presenting with infection with cytopenia and hemophagocytosis during initial nutritional therapy. She developed pyrexia, abdominal pain, and diarrhea during inpatient treatment. Although intravenous antibiotics were administered, the symptoms persisted. Acinetobacter baumannii was detected in blood culture. Hemophagocytosis was present in the bone marrow. Gamma globulin therapy was effective, with improvement in symptoms and cytopenia.

Conclusions

Although our case did not fulfill the criteria of hemophagocytic syndrome, clinicians should consider severe infection in anorexia nervosa with cytopenia and hemophagocytosis.