< Presentation of a case
>
A 28-year-old man sought medical
attention because of prolonged fever for 2 weeks. He had been
in good state of health until 2 weeks ago, when he began to
have high fevers; his temperature could be as high as 39.5℃
which was sometimes accompanied by chills, profound fatigue,
and malaise. The fevers could be relieved temporarily by
acetaminophen. There was no diurnal or nocturnal pattern.
There was no sore throat, rhinorrhea, cough, dyspnea, nausea,
vomiting, dizziness, photophobia, diarrhea, constipation,
abdominal pain, joint pain, night sweats or weight loss.
Because of prolonged fever, he visited our clinic for help.
He was a pharmaceutical
representative and denied any other disease. There was no
history of smoking, alcohol drinking, allergy, animal contact,
recent travel, transfusion, tattoo, illicit drug use,
commercial sex or homosexuality.
On physical examination, he had
clear consciousness but was ill-looking. His height was 175 cm
and weight was 75 kg. The temperature was 38.3°C, the pulse
rate was 113 beats per minute and the respiratory rate was 16
breaths per minute. His blood pressure while in supine
position was 136/77 mmHg. His conjunctivae were pink, and the
sclerae were anicteric. The pupils were isocoric with prompt
light reflexes. There was no oral thrush or oral ulcers in the
oral cavity. The neck was supple without lymphadenopathy,
engorged jugular veins, palpable thyroid gland or carotid
bruits. The chest wall expansion was symmetric, and breath
sounds were bilaterally clear. The heart beats were regular
without audible murmur. The abdomen was soft. Bowel sounds
were normoactive and liver and spleen were impalpable. His
extremities were freely movable without edema. There was no
cyanosis, petechiae, purpura or pigmentation. The genitalia
were free of ulcers and discharge.
< Laboratory data
>
1. CBC/DC
WBC |
HB |
PLT |
Seg |
Mono |
Lym |
Aty. lym |
K/μL |
g/dL |
K/μL |
% |
% |
% |
% |
3.4 |
13.4 |
172 |
46 |
8 |
36 |
10 |
2.
BCS+e-
ALB |
TP |
T-Bil |
AST |
ALT |
ALP |
γ-GT |
g/dL |
g/dL |
mg/dL |
U/L |
U/L |
U/L |
U/L |
4.0 |
7.0 |
0.6 |
268 |
526 |
190 |
53 |
UN |
CRE |
Na+ |
K+ |
CRP |
Glucose |
LDH |
mg/dL |
mg/dL |
mmol/L |
mmol/L |
mg/dL |
mg/dL |
U/L |
10.1 |
0.7 |
138 |
4.2 |
0.9 |
110 |
1268 |
3. Urine analysis
Appearance |
Sp. Gr |
pH |
Protein |
Glucose |
Ketone |
OB |
|
|
|
g/dL |
mg/dL |
|
|
Y;C |
1.02 |
6.5 |
- |
- |
- |
- |
Urobilirubin |
Bilirubin |
Nitrate |
WBC |
RBC |
Epi |
Cast |
|
|
|
|
|
HPF |
|
1.0 |
- |
- |
0-1 |
0-1 |
0-1 |
- |
4. Other tests
EBV- VCA-IgG |
EBV- VCA-IgM |
CMV IgM |
CMV IgG |
Anti-HIV |
1 :80(+) |
1 :10(-) |
+ |
1 :4 (-) |
- |
IgM anti-HAV |
IgG anti-HAV |
IgM anti-HBc |
Anti-HBs |
HBs Ag |
- |
- |
- |
+ |
- |
Anti-HBc |
Anti-HCV |
Toxoplasma IgM |
Toxoplasma IgG |
+ |
- |
- |
<6.5 |
EBV = Epstein-Barr virus; VCA = viral capsid antigen; Ig G
= immunoglobulin G; IgM = immunoglobulin M; CMV =
cytomegalovirus; HIV = human immunodeficiency virus;
HAV=hepatitis A virus ; HBc= hepatitis B core antigen ; HBs Ag
=hepatitis B surface antigen ; HBV hepatitis B virus ; HCV =
hepatitis C
virus.
< Course and treatment
>
Relative lymphocytosis in
peripheral blood sample with more than 10% atypical
lymphocytosis was reported and infectious mononucleosis was
diagnosed. Because IgM for EBV-VCA was negative and IgM for
CMV was positive, infectious mononucleosis due to CMV
infection was diagnosed. Supportive management with regular
acetaminophen and hydration was given. Follow-up IgG for CMV
turned positive four weeks later. The levels of
aminotransferases decreased gradually. He was discharged in a
stable condition.
< Discussion
>
臨床上病患出現持續發燒的時間延長,周邊血液檢查有相對較高數量(超過50%)的單核細胞(mononuclear
cells,包括淋巴球及單核球),且不典型淋巴球(atypical
lymphocyte)超過10%,即可診斷為傳染性單核球過多症(infectious
mononucleosis)。79%的傳染性單核球過多症是由Epstein-Barr virus
(EBV)所引起,而剩下的多為急性巨細胞病毒感染(acute cytomegalovirus
infection)所致,稱為CMV mononucleosis。其他更少見原因包括愛滋病毒(human
immunodeficiency virus)、肝炎病毒、及弓漿蟲(Toxoplasma gondii)感染。
CMV
mononucleosis可以發生於任何年紀,尤其好發於性行為頻繁的年輕成人,為接觸性傳染;潛伏期約20至60天,病程可持續2至6週,會有較長時間的高燒,有時會伴隨著寒顫、極度無力。常常出現肌肉酸痛、頭痛及脾臟腫大。相對於EB病毒常會造成的喉嚨痛、滲出性咽炎、及頸部淋巴腺腫大,在CMV
mononucleosis病患反而少見。少數病人會出現德國麻疹樣疹(rubelliform
rash)、肺炎、肋膜炎、心肌炎、關節炎及腦炎。
實驗室檢查可以發現相對多的淋巴球,而總白血球數可能是低、正常或偏高;雖然黃疸不常見,但是肝功能指數(serum
aminotransferase & alkaline
phosphatase)常常是上升的。異質性抗體(heterophil
antibody)呈陰性、EBV的IgM呈陰性,且CMV的IgM呈陽性,即可診斷為CMV
mononucleosis。亦可能短暫地出現冷凝球蛋白(cryglobulins)、類風濕性因子(rheumatoid
factors)、冷凝集素(cold agglutinins),及抗核抗體(antinuclear
antibody)。非常少數的情況下會出現溶血性貧血、血小板過低及白血球過低。
CMV
mononucleosis是一種自限性疾病,只需要支持性治療,一般不會留下後遺症。但是在非常少數情況也可能致死。可以持續數個月至數年在病患的尿液、生殖器分泌物及唾液中發現CMV。
< Reference
>
- Cytomegalovirus. Am Fam Physician
2003;67:519.
- Mandell GL, Douglas RG, Bennett JE. Mandell, Douglas,
and Bennett's Principles and practice of infectious
diseases. 5th ed. Philadelphia: Churchill Livingstone, 2000.
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