Fibromyalgia and parvovirus infection

Erythema Infectiosum: A Narrative Review

BACKGROUND

Erythema infectiosum occurs worldwide. School-aged children are most often affected. Since the diagnosis is mainly clinical, physicians should be well-versed in the clinical manifestations of erythema infectiosum to avoid misdiagnosis, unnecessary investigations, and mismanagement of the disease.

OBJECTIVES

The purpose of this article is to familiarize physicians with the wide spectrum of clinical manifestations and complications of erythema infectiosum associated with parvovirus B19 infection.

METHODS

A search was conducted in July 2022 in PubMed Clinical Queries using the key terms "Erythema infectiosum" OR "Fifth disease" OR "Slapped cheek disease" OR "Parvovirus B19". The search strategy included all clinical trials, observational studies, and reviews published within the past 10 years. Only papers published in the English literature were included in this review. The information retrieved from the above search was used in the compilation of the present article.

RESULTS

Erythema infectiosum is a common exanthematous illness of childhood caused by parvovirus B19. Parvovirus B19 spreads mainly by respiratory tract secretions and, to a lesser extent, the saliva of infected individuals. Children between 4 and 10 years of age are most often affected. The incubation period is usually 4 to 14 days. Prodromal symptoms are usually mild and consist of lowgrade fever, headache, malaise, and myalgia. The rash typically evolves in 3 stages. The initial stage is an erythematous rash on the cheeks, with a characteristic "slapped cheek" appearance. In the second stage, the rash spreads concurrently or quickly to the trunk, extremities, and buttocks as diffuse macular erythema. The rash tends to be more intense on extensor surfaces. The palms and soles are typically spared. Central clearing of the rash results in a characteristic lacy or reticulated appearance. The rash usually resolves spontaneously within three weeks without sequelae. The third stage is characterized by evanescence and recrudescence. In adults, the rash is less pronounced than that in children and is often atypical. Only approximately 20% of affected adults have an erythematous rash on the face. In adults, the rash is more frequently found on the legs, followed by the trunk, and arms. A reticulated or lacy erythema is noted in 80% of cases which helps to distinguish erythema infectiosum from other exanthems. Pruritus is noted in approximately 50% of cases. The diagnosis is mainly clinical. The many manifestations of parvovirus B19 infection can pose a diagnostic challenge even to the best diagnostician. Complications include arthritis, arthralgia, and transient aplastic crisis. In most cases, treatment is symptomatic and supportive. When parvovirus B19 infection occurs in pregnant women, hydrops fetalis becomes a real concern.

CONCLUSION

Erythema infectiosum, the most common clinical manifestation of parvovirus B19 infection, is characterized by a "slapped cheek" appearance on the face and lacy exanthem on the trunk and extremities. Parvovirus B19 infection is associated with a wide spectrum of clinical manifestations. Physicians should be aware of potential complications and conditions associated with parvovirus B19 infection, especially in individuals who are immunocompromised, chronically anemic, or pregnant.

Infection Elicited Autoimmunity and Myalgic Encephalomyelitis/Chronic Fatigue Syndrome: An Explanatory Model

Myalgic encephalomyelitis (ME) often also called chronic fatigue syndrome (ME/CFS) is a common, debilitating, disease of unknown origin. Although a subject of controversy and a considerable scientific literature, we think that a solid understanding of ME/CFS pathogenesis is emerging. In this study, we compiled recent findings and placed them in the context of the clinical picture and natural history of the disease. A pattern emerged, giving rise to an explanatory model. ME/CFS often starts after or during an infection. A logical explanation is that the infection initiates an autoreactive process, which affects several functions, including brain and energy metabolism. According to our model for ME/CFS pathogenesis, patients with a genetic predisposition and dysbiosis experience a gradual development of B cell clones prone to autoreactivity. Under normal circumstances these B cell offsprings would have led to tolerance. Subsequent exogenous microbial exposition (triggering) can lead to comorbidities such as fibromyalgia, thyroid disorder, and orthostatic hypotension. A decisive infectious trigger may then lead to immunization against autoantigens involved in aerobic energy production and/or hormone receptors and ion channel proteins, producing postexertional malaise and ME/CFS, affecting both muscle and brain. In principle, cloning and sequencing of immunoglobulin variable domains could reveal the evolution of pathogenic clones. Although evidence consistent with the model accumulated in recent years, there are several missing links in it. Hopefully, the hypothesis generates testable propositions that can augment the understanding of the pathogenesis of ME/CFS.

Human Parvoviruses

Parvovirus B19 (B19V) and human bocavirus 1 (HBoV1), members of the large Parvoviridae family, are human pathogens responsible for a variety of diseases. For B19V in particular, host features determine disease manifestations. These viruses are prevalent worldwide and are culturable in vitro, and serological and molecular assays are available but require careful interpretation of results. Additional human parvoviruses, including HBoV2 to -4, human parvovirus 4 (PARV4), and human bufavirus (BuV) are also reviewed. The full spectrum of parvovirus disease in humans has yet to be established. Candidate recombinant B19V vaccines have been developed but may not be commercially feasible. We review relevant features of the molecular and cellular biology of these viruses, and the human immune response that they elicit, which have allowed a deep understanding of pathophysiology.

Dietary Modifications and Fibromyalgia

Fibromyalgia (FM) is a common rheumatic condition with an unknown etiology. The role of diet in the treatment of FM has been the subject of a small but growing body of research, particularly in Scandinavian nations, with results showing benefits in pain reduction, sleep quality, and general health. Removal of dietary excitotoxins, alteration of cytokines, reduced oxidative stress, improved bowel flora, and central nervous system chemical modification may result from dietary modifications in FM. Based on this review of the literature, it can be concluded that dietary modification may provide relief in a subset of FM patients and certainly warrants further investigation.

Fibromyalgia syndrome: etiology, pathogenesis, diagnosis, and treatment

Fibromyalgia syndrome is mainly characterized by pain, fatigue, and sleep disruption. The etiology of fibromyalgia is still unclear: if central sensitization is considered to be the main mechanism involved, then many other factors, genetic, immunological, and hormonal, may play an important role. The diagnosis is typically clinical (there are no laboratory abnormalities) and the physician must concentrate on pain and on its features. Additional symptoms (e.g., Raynaud's phenomenon, irritable bowel disease, and heat and cold intolerance) can be associated with this condition. A careful differential diagnosis is mandatory: fibromyalgia is not a diagnosis of exclusion. Since 1990, diagnosis has been principally based on the two major diagnostic criteria defined by the ACR. Recently, new criteria have been proposed. The main goals of the treatment are to alleviate pain, increase restorative sleep, and improve physical function. A multidisciplinary approach is optimal. While most nonsteroidal anti-inflammatory drugs and opioids have limited benefit, an important role is played by antidepressants and neuromodulating antiepileptics: currently duloxetine (NNT for a 30% pain reduction 7.2), milnacipran (NNT 19), and pregabalin (NNT 8.6) are the only drugs approved by the US Food and Drug Administration for the treatment of fibromyalgia. In addition, nonpharmacological treatments should be associated with drug therapy.

Helicobacter pylori seropositivity in fibromyalgia syndrome

Although there are some studies suggesting relation between different types of infection and fibromyalgia syndrome (FM), there is presently no proof that FM is caused by an infection. Helicobacter pylori (HP) infection may cause extragastric manifestations. Inflammation is an important mediator of increased sympathetic nervous system activity and may lead to pain in fibromyalgia patients. In this study, we aimed to investigate the HP seropositivity in fibromyalgia patients compared with controls for possible role of HP infection in FM. Sixty-seven patients with fibromyalgia were evaluated. Two of them were excluded from the study because of high level of acute phase reactants. Sixty-five female patients with fibromyalgia and 41 randomly selected age-matched female healthy controls were enrolled to study. Serum HP IgA and IgG antibodies were measured by enzyme-linked immunosorbent assay technique. Fibromyalgia Impact Questionnaire was assessed in patients and controls. Seropositivity of HP IgG antibody in the fibromyalgia patients was significantly higher than in the control group. No statistically significant differences were found regarding the clinical features between fibromyalgia patients with HP IgG antibody and patients without IgG antibody. Our study suggests that former HP infection may have a role in the etiopathogenesis of fibromyalgia syndrome or may act as a triggering factor. However, high seroprevalence of HP in general population and prevalent asymptomatic infection make it difficult to interpret these results for the definite role of HP in FM. Highlighting the pathophysiologic mechanisms of FM will result in more effective treatment regimens.

Seroprevalence of parvovirus B19 in fibromyalgia syndrome

This study was aimed to evaluate the seroprevalence of parvovirus B19 in patients with fibromyalgia syndrome (FS). Seventy-five patients with FS (44.3 +/- 8.3) and 75 healthy controls (44.2 +/- 8.1) were evaluated. Serum anti-B19 IgM and IgG antibodies were measured by ELISA technique. Patients were questioned about duration of symptoms, characteristic features of FS, and symptoms related with viral infection preceding the onset of FS. No significant difference was found regarding the prevalence of anti-B19 IgM antibodies between the groups (p = 0.494). Seropositivity of anti-B19 IgG of the patients was significantly higher than control group (81.3% vs. 64% respectively, p = 0.027). No statistically significant differences were found regarding to the clinical features between fibromyalgia patients with IgG antibody compared to those without IgG antibody. Parvovirus B19 IgG seropositivity was found to be significantly higher in patients with FS. Parvovirus B19 infection might have a role in the etiopathogenesis of FS or might act as a triggering factor.

Fibromyalgia, sleep disorder and chronic fatigue syndrome

Various research studies show that the amalgam of disordered sleep physiology, chronic fatigue, diffuse myalgia, and cognitive and behavioural symptoms constitutes a non-restorative sleep syndrome that may follow a febrile illness, as in the chronic fatigue syndrome. Where rheumatic complaints are prominent such a constellation of disturbed sleep physiology and symptoms also characterizes the fibromyalgia disorder. In contrast to the chronic fatigue syndrome, fibromyalgia is associated with a variety of initiating or perpetuating factors such as psychologically distressing events, primary sleep disorders (e.g. sleep apnoea, periodic limb movement disorder) and inflammatory rheumatic disease, as well as an acute febrile illness. The chronic fatigue syndrome and fibromyalgia have similar disordered sleep physiology, namely an alpha rhythm disturbance (7.5-11 Hz) in the electroencephalogram (EEG) within non-rapid eye movement (NREM) sleep that accompanies increased nocturnal vigilance and light, unrefreshing sleep. Aspects of cytokine and cellular immune functions are shown to be related to the sleep-wake system. The evidence suggests a reciprocal relationship of the immune and sleep-wake systems. Interference either with the immune system (e.g. by a viral agent or by cytokines such as alpha-interferon or interleukin 2) or with the sleeping-waking brain system (e.g. by sleep deprivation) has effects on the other system and will be accompanied by the symptoms of the chronic fatigue syndrome.

Is human herpesvirus-6 a trigger for chronic fatigue syndrome?

Chronic fatigue syndrome (CFS) is an illness currently defined entirely by a combination of non-specific symptoms. Despite this subjective definition, CFS is associated with objective underlying biological abnormalities, particularly involving the nervous system and immune system. Most studies have found that active infection with human herpesvirus-6 (HHV-6)--a neurotropic, gliotropic and immunotropic virus--is present more often in patients with CFS than in healthy control and disease comparison subjects, yet it is not found in all patients at the time of testing. Moreover, HHV-6 has been associated with many of the neurological and immunological findings in patients with CFS. Finally, CFS, multiple sclerosis and seizure disorders share some clinical and laboratory features and, like CFS, the latter two disorders also are being associated increasingly with active HHV-6 infection. Therefore, it is plausible that active infection with HHV-6 may trigger and perpetuate CFS in a subset of patients.

Fibromyalgia Frequency in Hepatitis B Carriers

BACKGROUND

Fibromyalgia (FM) is characterized by diffuse musculoskeletal pain, fatigue, morning stiffness, and sleep disturbance. Chronic viral infections may trigger FM symptoms.

OBJECTIVES

In this study, we aimed to evaluate whether there was an association between HBsAg seropositivity and fibromyalgia syndrome.

METHODS

Fifty hepatitis B carriers (HBsAg positivity and anti-HBs negativity in sera for at least 6 months) and 50 age- and sex-matched HbsAg-negative control subjects were enrolled in this study. The hepatitis B carriers with normal or slightly elevated aspartate aminotransferase (AST) and alanine aminotransferase (ALT) levels were recruited from the infectious diseases outpatient clinic and the control group was recruited from the physical medicine and rehabilitation outpatient clinic. The relationship between groups was calculated by independent Student t test, chi-squared test, and Fisher exact test for comparing proportions. Alpha criterion for significance was set at P < 0.05.

RESULTS

There was no statistically significant difference between the groups according to sex, mean age, body mass index, serum ALT, and AST levels (P > 0.05). FM syndrome and FM-associated symptoms were much more prevalent in the hepatitis B group (P < 0.001).

CONCLUSION

The present study suggests that chronic hepatitis B carriage appears to increase the risk of FM and many of the typically associated symptoms. Whether this association is related to altered liver function, viral infection, concerns associated with chronic disease, or other factors, physicians should be aware of this apparent association.

Fibromyalgia, hepatitis C infection, and the cytokine connection

Fibromyalgia and chronic hepatitis C infection share many clinical features including prominent somatic complaints such as musculoskeletal pain and fatigue. There is a growing body of evidence supporting a link between cytokines and somatic complaints. This review discusses alterations of cytokines in fibromyalgia, including increased serum levels of interleukin (IL)-2, IL-2 receptor, IL-8, IL-1 receptor antagonist; increased IL-1 and IL-6 produced by stimulated peripheral blood mononuclear cell in patients with FM for longer than 2 years; increased gp130, which is a neutrophil cytokine transducing protein; increased soluble IL-6 receptor and soluble IL-1 receptor antagonist only in patients with fibromyalgia who are depressed; and IL-1 beta, IL-6, and TNF-a by reverse transcriptase-polymerase chain reaction in skin biopsies of some patients with fibromyalgia. In addition, this review describes the mechanism by which alterations in cytokines in fibromyalgia and chronic hepatitis C infection can produce hyperalgesia and other neurally mediated symptoms through the presence of cytokine receptors on glial cells and opiate receptors on lymphocytes and the influence of cytokines on the hypothalamus-pituitary-adrenal axis such as IL-1, IL-6, and TNF-a activating and IL-2 and IFN-a down-regulating the HPA axis, respectively. The association between chronic hepatitis C infection and fibromyalgia is discussed, including a description of key cytokine changes in chronic hepatitis C infection. Future studies are encouraged to further characterize these immunologic alterations with potential pathophysiologic and therapeutic implications.

Cytokines in parvovirus B19 infection as an aid to understanding chronic fatigue syndrome

Human parvovirus B19 infection has been associated with various clinical manifestations of a rheumatic nature such as arthritis, fatigue, and chronic fatigue syndrome (CFS), which can persist for years after the acute phase. The authors have demonstrated recently that acute B19 infection is accompanied by raised circulating levels of IL-1b, IL-6, TNF-a, and IFN-g and that raised circulating levels of TNF-a and IFN-g persist and are accompanied by MCP-1 in those patients who develop CFS. A resolution of clinical symptoms and cytokine dysregulation after intravenous immunoglobulin (IVIG) therapy, which is the only specific treatment for parvovirus B19 infection, also has been reported. Although CFS may be caused by various microbial and other triggers, that triggered by B19 virus is clinically indistinguishable from idiopathic CFS and exhibits similar cytokine abnormalities and may represent an accessible model for the study of CFS.

Rheumatic mimics and selected triggers of fibromyalgia

Fibromyalgia is a chronic pain syndrome of unknown etiology characterized by diffuse pain and tender points, which have been present for more than 3 months. Many patients with systemic illnesses can have diffuse pain similar to that found in fibromyalgia, including rheumatic diseases such as polymyalgia rheumatica, rheumatoid arthritis, idiopathic inflammatory myopathy, systemic lupus erythematosus, and joint hypermobility. Osteomalacia and thyroid disease are also in the differential diagnosis of diffuse pain and are imminently treatable. In addition, there has been interest throughout the past 10 years in infectious diseases including hepatitis C, Lyme disease, coxsackie B, HIV, and parvovirus infection, which may cause or trigger fibromyalgia. This paper provides a framework to use when identifying these diseases as part of the evaluation of a patient with chronic widespread musculoskeletal pain.

Sleep and pain

Noxious stimuli and painful disorders interfere with sleep, but disturbances in sleep also contribute to the experience of pain.Chronic paroxysmal hemicrania and possibly cluster headaches are related to REM sleep. Whereas headache is associated with snoring and sleep apnea, morning headaches are not specific for any primary sleep disorder. Nevertheless, the management of the sleep disorder ameliorates both morning headache and migraine.Noxious stimuli administered into muscles during slow-wave sleep (SWS) result in decreases in delta and sigma but an increase in alpha and beta EEG frequencies during sleep. Noise stimuli that disrupt SWS result in unrefreshing sleep, diffuse musculoskeletal pain, tenderness, and fatigue in normal healthy subjects. Such symptoms accompany alpha EEG sleep patterns that often occur in patients with fibromyalgia. The alpha EEG patterns include phasic and tonic alpha EEG sleep as well as periodic K alpha EEG sleep or frequent periodic cyclical alternating pattern. Moreover, alpha EEG sleep, as well as sleep-related breathing disorder and periodic limb movement disorder, occur in some patients with fibromyalgia, rheumatoid arthritis and osteoarthritis. Depression and not alpha EEG sleep are features of somatoform pain disorder. Disturbances in sleep, pain behaviour and psychological distress influence return to work in workers who have suffered a soft tissue injury, e.g. low back pain. Patients with irritable bowel disorder have disturbed sleep and have increased REM sleep. In conclusion, there is a reciprocal relationship between sleep quality and pain. The recognition of disturbed or unrefreshing sleep influences the management of painful medical disorders.

Clinical illness due to parvovirus B19 infection after infusion of solvent/detergent-treated pooled plasma

BACKGROUND

Lipid-enveloped viruses such as HIV, HBV, and HCV can be inactivated by treatment with solvents and detergents. HAV and human parvovirus B19 lack lipid envelopes and are not inactivated. Solvent/detergent-treated pooled plasma (S/D plasma) contains neutralizing antibodies, but it is not known whether the parvovirus B19 antibody content is sufficient to prevent transmission of the disease. A patient is described who developed a clinical illness due to parvovirus B19 infection after the infusion of S/D plasma.

CASE REPORT

A 36-year-old woman with myasthenia gravis underwent five plasma exchange procedures from January 15 to January 25, 1999, using albumin, except for 5 units of SD plasma given because of a low fibrinogen level. Four of the 5 units were implicated in a recall after high levels of parvovirus B19 DNA were found in several lots. Two weeks after the infusion, the patient developed fatigue, a rash, and severe polyarthralgias. Parvovirus B19 IgG and IgM antibody titers were consistent with an acute infection.

CONCLUSION

Clinically apparent parvovirus B19 infection can follow the use of S/D plasma that contains high levels of parvovirus B19 DNA.

Raynaud's phenomenon as a manifestation of parvovirus B19 infection: case reports and review of parvovirus B19 rheumatic and vasculitic syndromes

Infection with human parvovirus B19 is manifested as erythema infectiosum, transient aplastic crisis, or hydrops fetalis. Rheumatic manifestations include arthropathy and various vasculitic syndromes. Isolated Raynaud's phenomenon due to parvovirus B19 has never been described. We report on 2 previously healthy sisters with new-onset Raynaud's phenomenon accompanied by severe generalized polyarthralgia. A full workup was negative, except serology for parvovirus B19, which was positive. All symptoms gradually subsided within 3-5 months, and no recurrence has been noted during the 3 years since onset. We review all the studies in the English-language literature on parvovirus B19-induced rheumatic and vasculitic syndromes. We hypothesize that the pathogenesis of Raynaud's phenomenon in our patients involved immune-mediated endothelial damage leading to platelet activation and vasoconstriction. We recommend that in cases of unexplained Raynaud's phenomenon, serology for parvovirus B19 be included in the evaluation.

Emerging concepts in the neurobiology of chronic pain: evidence of abnormal sensory processing in fibromyalgia

Chronic pain often differs from acute pain. The correlation between tissue pathology and the perceived severity of the chronic pain experience is poor or even absent. Furthermore, the sharp spatial localization of acute pain is not a feature of chronic pain; chronic pain is more diffuse and often spreads to areas beyond the original site. Of importance, chronic pain seldom responds to the therapeutic measures that are successful in treating acute pain. Physicians who are unaware of these differences may label the patient with chronic pain as being neurotic or even a malingerer. During the past decade, an exponential growth has occurred in the scientific underpinnings of chronic pain states. In particular, the concept of nonnociceptive pain has been refined at a physiologic, structural, and molecular level. This review focuses on this new body of knowledge, with particular reference to the chronic pain state termed "fibromyalgia."

Rheumatic manifestations of parvovirus B19 infection

Human parvovirus B19 is an emerging DNA virus. B19 infection is common and widespread. Major manifestations of B19 infection are transient aplastic crisis, erythema infectiosum, hydrops fetalis, acute and chronic rheumatoid-like arthropathy, and, in the immunocompromised host, chronic or recurrent bone marrow suppression. A number of less common manifestations of B19 infection include various rash illnesses, neuropathies, and acute fulminant liver failure. Of rheumatologic interest, B19 infection must be differentiated from early presentation of more classic erosive rheumatoid arthritis and, in some cases, systemic lupus erythematosus. It is unlikely that B19 plays a role in classic erosive rheumatoid arthritis, but understanding pathogenesis of B19 arthropathy may provide insights into the mechanisms by which rheumatoid arthritis develops. Evidence for persistence of B19 infection suggests that human parvovirus B19 infection may serve as a model for the study of virus-host interactions and the role of viruses in the pathogenesis of rheumatic diseases.

Increased rates of fibromyalgia following cervical spine injury. A controlled study of 161 cases of traumatic injury

OBJECTIVE

To study the relationship between cervical spine injury and the development of fibromyalgia syndrome (FMS).

METHODS

One hundred two patients with neck injury and 59 patients with leg fractures (control group) were assessed for nonarticular tenderness and the presence of FMS. A count of 18 tender points was conducted by thumb palpation; and tenderness thresholds were assessed by dolorimetry at 9 tender sites. All patients were interviewed about the presence and severity of neck and FMS-related symptoms. FMS was diagnosed using the American College of Rheumatology 1990 criteria. Additional questions assessed measures of physical functioning and quality of life (QOL).

RESULTS

Although no patient had a chronic pain syndrome prior to the trauma, FMS was diagnosed following injury in 21.6% of those with neck injury versus 1.7% of the control patients with lower extremity fractures (P = 0.001). Almost all symptoms were more common and severe in the group with neck injury. FMS was noted at a mean of 3.2 months (SD 1.1) after the trauma. Neck injury patients with FMS (n = 22) had more tenderness, had more severe and prevalent FMS-related symptoms, and reported lower QOL and more impaired physical functioning than did those without FMS (n = 80). In spite of the injury or the presence of FMS, all patients were employed at the time of examination. Twenty percent of patients with neck injury and 24% of patients with leg fractures filed an insurance claim. Claims were not associated with the presence of FMS, increased FMS symptoms, pain, or impaired functioning.

CONCLUSION

FMS was 13 times more frequent following neck injury than following lower extremity injury. All patients continued to be employed, and insurance claims were not increased in patients with FMS.

Human parvovirus B19 and blood products

BACKGROUND AND OBJECTIVES

Human B19 parvovirus (B19), identified in 1975, was only recognised as the causative agent of fifth disease in 1983. The incidence of viraemia is low, around 1 in 1,000, but is sufficient to ensure that most plasma pools for fractionation contain some virus. While infection usually occurs in childhood and is benign, chronic infection sometimes occurs and may be of concern in certain patient groups.

MATERIALS AND METHODS

This review is based on a meeting held in March 1995, and addresses recent concerns regarding the potential transmission of B19 infection by pooled plasma products.

RESULTS

Recent data on the pathophysiology and assay of this virus are summarised along with possible approaches to donor screening, product screening, and virus removal. Only five cases of symptomatic infection have been reported in persons with haemophilia, but no technology for virus removal is established, and infection may be of concern in pregnant women, and in patients with enhanced red cell turnover or who are immunosuppressed, including those infected with human immunodeficiency virus, but only rarely in immunocompetent patients.

CONCLUSIONS

For the future, well-validated assays relevant to virus infectivity are required if blood donations, plasma pools, or plasma products are to be screened, and an in-process virus inactivation step for B19 would be highly desirable. In the interim, non-plasma or recombinant products or a selective transfusion policy might be used in patient groups in which B19 infection is of particular concern. Further clinical data on the prognosis and impact of B19 infection are needed to justify both such policies and the future adoption of new technologies designed to reduce any excess B19 infectivity arising from transfused products.

Fibromyalgia and chronic fatigue syndrome: similarities and differences

CFS and FM are clinical conditions characterized by a variety of nonspecific symptoms including prominent fatigue, myalgia, and sleep disturbances. There are no diagnostic studies or widely accepted, pathogenic, explanatory models for either illness. Despite remarkably different diagnostic criteria, CFS and FM have many demographic and clinical similarities. More specifically, few differences exist in the domains of symptoms, examination findings, laboratory tests, functional status, psychosocial features, and psychiatric disorders. FM appears to represent an additional burden of suffering among those with CFS, however, underscoring the importance of recognizing concurrent CFS and FM. Further clarification of the similarities (and differences) between CFS and FM may be useful in studies of prognosis and help define subsets of patients who may benefit from specific therapeutic interventions.

Bowel dysfunction and irritable bowel syndrome in fibromyalgia patients

Fibromyalgia and irritable bowel syndrome are both common conditions which account for most of the referrals to physical medicine and rehabilitation-rheumatology and gastroenterology clinics, and they frequently coexist. In this study, we utilized a previously validated questionnaire to assess the prevalence of symptoms of bowel dysfunction and irritable bowel syndrome, and to survey the range of bowel pattern in 75 patients with fibromyalgia as compared to 50 normal controls. Symptoms associated with irritable bowel syndrome (p < 0.05) were reported in 41.8% of the fibromyalgia patients and 16% of the normal controls. In conclusion, we found that patients with fibromyalgia have a high prevalence of gastrointestinal complaints confirming the results indicating that fibromyalgia and irritable bowel syndrome frequently coexist. This may suggest a common pathogenic mechanism for both conditions.

Absence of parvovirus B19 infection in chronic fatigue syndrome

OBJECTIVE

To evaluate the presence of infection with parvovirus B19 in patients with chronic fatigue syndrome (CFS) who also had rheumatologic symptoms and mild hematologic abnormalities.

METHODS

Seven patients meeting the Centers for Disease Control and Prevention working case definition for CFS who also had mild leukopenia, thrombocytopenia, or anemia were studied. Bone marrow was aspirated from each patient, and examined for morphologic abnormalities, including features seen in marrow infections with parvovirus B19, as well as for parvoviral DNA, using polymerase chain reaction (PCR) amplification. Serum obtained at the time of marrow aspiration was also evaluated for parvoviral DNA, using the PCR method, and was examined for the presence of IgM and IgG antibodies to the virus.

RESULTS

No evidence of marrow involvement with parvovirus B19 was found in any patient. One patient had antibody evidence of a transient parvoviral infection, during which time an underlying thrombocytopenia worsened.

CONCLUSION

Despite examining a selected group of patients thought most likely to have parvoviral infection, based on clinical and hematologic measures, no evidence of clinically important parvoviral infection was noted. Thus, it seems unlikely that parvovirus B19 plays a role in CFS, even though it has been associated with fibromyalgia, a clinically similar syndrome.

B19 parvovirus

B19 parvovirus is pathogenic in man and causes a variety of clinical illnesses, among them several haematological diseases. Acute infection of a host with underlying haemolysis produces transient aplastic crisis; of the midtrimester fetus, hydrops fetalis; and of an immunocompromised patient, pure red cell aplasia. The target of B19 parvovirus infection is the human erythroid progenitor cell. Infection is cytotoxic due to expression of the viral nonstructural protein. The virus can be propagated in cultures of human bone marrow, blood, and fetal liver. Humoral immunity normally terminates infection, and commercially available immunoglobulin can be used to treat persistent infection. Recombinant capsids, produced in a baculovirus system, are suitable as a vaccine reagent.

Sleep, neuroimmune and neuroendocrine functions in fibromyalgia and chronic fatigue syndrome

The justification for disordered chronobiology for fibromyalgia and chronic fatigue syndrome (CFS) is based on the following evidence: The studies on disordered sleep physiology and the symptoms of fibromyalgia and CFS; the experimental studies that draw a link between interleukin-1 (IL-1), immune-neuroendocrine-thermal systems and the sleep-wake cycle; studies and preliminary data of the inter-relationships of sleep-wakefulness, IL-1, and aspects of peripheral immune and neuroendocrine functions in healthy men and in women during differing phases of the menstrual cycle; and the observations of alterations in the immune-neuroendocrine functions of patients with fibromyalgia and CFS (Moldofsky, 1993b, d). Time series analyses of measures of the circadian pattern of the sleep-wake behavioural system, immune, neuroendocrine and temperature functions in patients with fibromyalgia and CFS should determine whether alterations of aspects of the neuro-immune-endocrine systems that accompany disordered sleep physiology result in nonrestorative sleep, pain, fatigue, cognitive and mood symptoms in patients with fibromyalgia and CFS.

Controlled trials of therapy in fibromyalgia syndrome

Many different interventions have been studied in the therapy of fibromyalgia syndrome (Tables 1 and 2). While most have been effective, in general these trials have been short term. Furthermore, important or substantial improvement, when it has been assessed, occurs in only small proportions of patients. Long-term, comparative trials of both efficacy and toxicity are necessary. Trials such as these require large numbers of patients (compared with placebo-controlled trials, which are generally impractical in long-duration trials due to the large numbers of dropouts in the placebo arm) and therefore are expensive and difficult to accomplish. Two other approaches offer potential solutions to the problem of adequate long-term comparative trials: (a) N-of-1 trials and (b) meta-analysis. N-of-1 trials have the advantage of random assignment, double-blinding and multiple potential comparisons in the same patient. Meta-analysis involves combining the results of studies, which individually may have conflicting results and lack adequate statistical power, to reach an overall result with sufficient statistical power to make meaningful conclusions, especially with respect to comparative efficacy. Peluso and colleagues (1993) have performed a recent meta-analysis of available therapies in fibromyalgia syndrome and found that the effect-size (a standardized measure of the efficacy of a given therapy) of several non-medication therapies such as electroacupuncture exceeded that of traditional medication therapies. Unfortunately, lack of uniformity in the use of outcome measures across included trials and the small numbers of comparable non-medication trials makes definitive conclusions regarding relative efficacy of therapies difficult. Nevertheless, application of meta-analytic methods such as these should facilitate future comparisons of different interventions. Ideally, future clinical trials in fibromyalgia syndrome should employ the same outcome measures to permit application of these methods. Few trials have assessed improvement in functional status. Functional status measures such as the HAQ (Fries et al., 1980), the Fibromyalgia Impact Questionnaire (Burckhardt et al, 1991) or similar instruments should be employed in future studies of therapy in fibromyalgia. Given that individual modalities appear to confer relatively modest benefit on average. Combination approaches are reasonable, although randomized, blinded trials to assess these approaches are methodologically complex. Several preliminary studies which have addressed this approach appear promising (see Chapter 12; Goldenberg et al, 1993). Finally, no studies have yet assessed the comparative cost-efficacy of available treatments. Controlled trials which address the cost-efficacy of commonly employed, but unproven treatments such as physiotherapy chiropractic manipulation and injection techniques are urgently needed.

Managing Fibromyalgia With Exercise

Although its cause remains obscure and no laboratory test confirms its diagnosis, fibromyalgia is a well-defined condition, more common than rheumatoid arthritis. Exercise is an essential component of treatment, helping patients cope with this painful disease.