Descriptive epidemiology of chronic fatigue syndrome based on a nationwide survey in Japan

Abstract:

In order to clarify the epidemiological features of chronic fatigue syndrome (CFS), a nationwide survey was conducted using the Japanese version of the CDC Criteria prepared by the CFS Research Group of Japan. All clinical departments of internal medicine, pediatrics, psychiatry and neurology at university hospitals and at ordinary hospitals with 200 or more beds were surveyed.

Major results were as follows: (1) Period prevalence adjusted for response rate was 0.85 (0.63 for males and 1.02 for females) per 100,000 population during the year 1992; (2) Based on the first and final dates of hospital visits, the prevalences on January 1 of 1992 and 1993 were 0.40 and 0.60 per 100,000 population, respectively, suggesting an increasing trend; (3) Reported new cases during 1992 were 301, and the response adjusted-incidence was estimated to be 0.46 per 100,000 person-years; (4) The proportion of post-infectious CFS cases was 14.8% for both sexes, and tended to be slightly higher among females than males, but was not related to age. Three clusterings of two cases were reported.

 

Source: Minowa M, Jiamo M. Descriptive epidemiology of chronic fatigue syndrome based on a nationwide survey in Japan. J Epidemiol. 1996 Jun;6(2):75-80. https://www.jstage.jst.go.jp/article/jea1991/6/2/6_2_75/_pdf (Full article)

 

Demonstration of Borna disease virus RNA in peripheral blood mononuclear cells derived from Japanese patients with chronic fatigue syndrome

Abstract:

CFS, a recently named heterogeneous disorder, is an illness of unknown etiology. The association of CFS with viral infections has been suggested. A common association between CFS and several viruses examined has not been confirmed.

Here, we centered on the possible link between CFS and BDV infection. By nested RT-PCR followed by hybridization, BDV RNA was demonstrated as a clear signal in PBMCs in 3 out of 25 CFS patients. The amplified cDNA fragments were cloned and sequenced. A total of 16 clones were studied. Intra-patients divergencies of the p24 were 2-9%, 3-20%, and 3-11% in the deduced amino acids. Inter-patient divergencies among the 16 clones were 3-24%. Antibodies to recombinant BDV p24 protein were detected in 6 CFS patients including one carrying BDV RNA.

Overall, these gave the prevalence of 32% (8/25) in Japanese CFS patients, suggesting that Japanese CFS is highly associated with active infection of BDV, or a related agent.

 

Source: Nakaya T, Takahashi H, Nakamura Y, Asahi S, Tobiume M, Kuratsune H, Kitani T, Yamanishi K, Ikuta K. Demonstration of Borna disease virus RNA in peripheral blood mononuclear cells derived from Japanese patients with chronic fatigue syndrome. FEBS Lett. 1996 Jan 8;378(2):145-9. http://onlinelibrary.wiley.com/doi/10.1016/0014-5793(95)01439-X/epdf (Full article)

 

Possible correlation between Borna disease virus infection and Japanese patients with chronic fatigue syndrome

Abstract:

Borna disease virus (BDV) is a neurotropic, as yet unclassified, non-segmented, negative-sense, single-strand RNA virus. Natural infection with this virus has been reported to occur in horses and sheep. In addition, antibodies to BDV in plasma or BDV RNA in peripheral blood mononuclear cells (PBMCs) were also found in patients with neuropsychiatric diseases. We describe here the possible link between the patients with chronic fatigue syndrome (CFS) and infection with BDV.

 

Source: Kitani T, Kuratsune H, Fuke I, Nakamura Y, Nakaya T, Asahi S, Tobiume M, Yamaguti K, Machii T, Inagi R, Yamanishi K, Ikuta K. Possible correlation between Borna disease virus infection and Japanese patients with chronic fatigue syndrome. Microbiol Immunol. 1996;40(6):459-62. http://www.ncbi.nlm.nih.gov/pubmed/8839433

 

Chronic active Epstein-Barr virus infection in children in Japan

Abstract:

The patients with chronic active Epstein-Barr virus infection (CAEBV) in childhood in Japan are described. Among 39 registered cases, 20 patients were males and 19 were females. Unlike the X-linked lymphoproliferative syndrome, there was no hereditary background.

The incidence of hypersensitivity to mosquito bites was high (31.3%) as a past history. Most patients exhibited hepatomegaly (92.3%), splenomegaly (87.2%) and fever (84.6%). The incidence of absent anti-EB virus nuclear antigen titres was unexpectedly low (17.1%). Lymphoreticular disorders and cardiovascular diseases were major complications.

Twenty-four (61.5%) patients died 6 months to 8 years after the onset, mainly of hepatic failure (eight cases), cardiac failure (five cases), virus-associated haemophagocytic syndrome (three cases) and haematological malignancies (two cases). This study reveals the CAEBV in Japan has several clinical features and should be informative for the pathogenesis of EB virus.

 

Source: Ishihara S, Okada S, Wakiguchi H, Kurashige T, Morishima T, Kawa-Ha K. Chronic active Epstein-Barr virus infection in children in Japan. Acta Paediatr. 1995 Nov;84(11):1271-5. http://www.ncbi.nlm.nih.gov/pubmed/8580625

 

Psychobehavioral and immunological characteristics of adult people with chronic fatigue and patients with chronic fatigue syndrome

Abstract:

The psychobehavioral responses and cellular immune function were investigated in healthy people (control, N = 21), adult people with chronic fatigue (fatigue-non-CFS group, N = 24), and patients with chronic fatigue syndrome (CFS, N = 10).

Based on psychobehavioral responses, the fatigue-non-CFS group had low general activity levels (p < .05) and slightly depressive tendencies (p < .01) compared with the control. They had many life event stresses (p < .05) and sleep disturbances (p < .01), and they could not cope appropriately with stresses.

The fatigue-non-CFS group also showed significantly lower natural killer (NK) cell activity (p < .01) and decreased numbers of CD16+ and CD56+ cells (p < .05). Compared with the fatigue-non-CFS group, patients with CFS had higher degrees of physical fatigue (p < .01) and more life event stresses (p < .05).

They had lower general activity levels and social introversion. They were also in a depressive state. NK cell activity and the numbers of CD16+ and CD56+ cells were significantly reduced in patients with CFS (p < .01).

These findings suggest that adult people with chronic fatigue may be in an intermediate state between the healthy control and patients with CFS in terms of psychobehavioral responses and low NK cell activity. We observed three cases in such an intermediate state in whom CFS subsequently developed.

 

Source: Masuda A, Nozoe SI, Matsuyama T, Tanaka H. Psychobehavioral and immunological characteristics of adult people with chronic fatigue and patients with chronic fatigue syndrome. Psychosom Med. 1994 Nov-Dec;56(6):512-8. http://www.ncbi.nlm.nih.gov/pubmed/7871106

 

Human herpesvirus-7 (HHV-7)

Abstract:

HHV-7 first isolated in 1990 from a healthy individual, is a ubiquitous agent. The second independent isolation of HHV-7 from a chronic fatigue syndrome patient was reported in 1992. The seroepidemiology of HHV-7 suggested that its prevalence rate in the U.S.A. population is > 85%; however, in Japan a low prevalence rate has been reported. HHV-7 can be more readily isolated from the saliva than HHV-6. The primary infection of HHV-7 appears later in life than HHV-6. No disease has been reported that is etiologically linked to HHV-7. HHV-7 is more closely related to HHV-6 and the human cytomegalovirus than other members of the human herpesvirus family.

 

Source: Ablashi DV, Berneman ZN, Kramarsky B, Asano Y, Choudhury S, Pearson GR. Human herpesvirus-7 (HHV-7). In Vivo. 1994 Jul-Aug;8(4):549-54. http://www.ncbi.nlm.nih.gov/pubmed/7893982

 

Chronic fatigue syndrome and psychiatric diseases

Abstract:

The chronic fatigue syndrome consists of a combination of non-specific symptoms. Some believe that the CFS is subcategory of major depression, because the symptoms are similar to those of major depression. We believe that the CFS is quite different from major depression or neurotic depression, since the CFS has no lack of initiative and effort, no inhibition which is seen in endogenous depression, and sharp fluctuations in general fatigue, anxiety, and various persisting somatic symptoms, such as, malaise and mild fever. CFS seems to be similar to the neurasthenia. It is harmful, at least, in aetiology and treatment, to neglect the diagnosis of the CFS.

 

Source: Matsuno T, Hikita K, Matsuo T. Chronic fatigue syndrome and psychiatric diseases. Nihon Rinsho. 1994 May;52(5):1339-44. [Article in Japanese] http://www.ncbi.nlm.nih.gov/pubmed/8007411

 

Acylcarnitine deficiency in chronic fatigue syndrome

Abstract:

One of the characteristic complaints of patients with chronic fatigue syndrome (CFS) is the skeletal muscle-related symptom. However, the abnormalities in the skeletal muscle that explain the symptom are not clear.

Herein, we show that our patients with CFS had a deficiency of serum acylcarnitine. As carnitine has an important role in energy production and modulation of the intramitochondrial coenzyme A (CoA)/acyl-CoA ratio in the skeletal muscle, this deficiency might induce an energy deficit and/or abnormality of the intramitochondrial condition in the skeletal muscle, thus resulting in general fatigue, myalgia, muscle weakness, and postexertional malaise in patients with CFS.

Furthermore, the concentration of serum acylcarnitine in patients with CFS tended to increase to the normal level with the recovery of general fatigue. Therefore, the measurement of acylcarnitine would be a useful tool for the diagnosis and assessment of the degree of clinical manifestation in patients with CFS.

 

Source: Kuratsune H, Yamaguti K, Takahashi M, Misaki H, Tagawa S, Kitani T. Acylcarnitine deficiency in chronic fatigue syndrome. Clin Infect Dis. 1994 Jan;18 Suppl 1:S62-7. http://www.ncbi.nlm.nih.gov/pubmed/8148455

 

Prevalence of human herpesvirus 6 variants A and B in patients with chronic fatigue syndrome

Abstract:

 

Peripheral blood mononuclear cells collected from 13 patients with chronic fatigue syndrome and 13 healthy controls were analyzed for the presence of human herpesvirus 6 (HHV-6) DNA by variant-specific polymerase chain reaction and dot blot hybridization. HHV-6 DNA was detected in 7 of 13 (53%) patients, and of those 7 patients, 4 were positive for HHV-6 variant A DNA and 3 were for variant B. No HHV-6 DNA was detected in the controls. Serum antibody titers to the late antigen and antibody prevalence to the early antigen of HHV-6 were significantly higher in the patient group. These results suggest active replication of HHV-6 in patients with chronic fatigue syndrome.

 

Source: Yalcin S1, Kuratsune H, Yamaguchi K, Kitani T, Yamanishi K. Prevalence of human herpesvirus 6 variants A and B in patients with chronic fatigue syndrome. Microbiol Immunol. 1994;38(7):587-90. http://onlinelibrary.wiley.com/doi/10.1111/j.1348-0421.1994.tb01827.x/pdf (Full article)

 

Japanese patients with chronic fatigue syndrome are negative for known retrovirus infections

Abstract:

Although chronic fatigue syndrome (CFS) is known to be the syndrome that begins with an acute flu-like illness that may be due to the exposure to an infectious agent, there has been no convincing evidence on the causative agents.

Recently, human T-lymphotropic virus type II (HTLV-II)-like virus has been reported to be associated with the CFS by using HTLV Western blot analysis and polymerase chain reaction. However, some investigators could not detect HTLV-II by indirect immunofluorescence analysis.

Lately, CFS patients have been reported in Japan. We detected all 30 tested patients with CFS were seronegative for HTLV-II, HTLV-I and HIV by specific peptide ELISA and Western blot. Further, PCR analysis was negative for HTLV-II and retrovirus was not detected by coculture method with patients’ PBMC. Thus, known human retrovirus infections do not cause a CFS in Japan.

 

Source: Honda M, Kitamura K, Nakasone T, Fukushima Y, Matsuda S, Nishioka K, Matsuda J, Hashimoto N, Yamazaki S. Japanese patients with chronic fatigue syndrome are negative for known retrovirus infections. Microbiol Immunol. 1993;37(10):779-84. http://www.ncbi.nlm.nih.gov/pubmed/7507200