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<Brief
History>
A 26 year-old man came to the emergency room because of a
3-day history of severe abdominal pain
This 26 year-old Taiwanese had had fever with persistent
localized, severe and sharp periumbilical cramping pain for 3
days and he visited local hospital for help. He was diagnosed
to have acute appendicitis and suggested to receive
appendectectomy, which then was performed smoothly. The
post-operative course was smooth, however, severe
periumbilical cramping pain and vomiting recurred days later.
Then he was transferred to a medical center for further
work-up. The periumbilical abdominal pain was severe,
persistent and cramping in character. It was aggravated by
food intake and relieved by analgesics. The associated
symptoms included nausea, vomiting, anorexia and abdominal
distention. His past medical history was insignificant. He
denied history of psychiatric illness, sexual intercourse,
smoking, drinking, or illicit drug use. Stool passage was
normal.
<Physical
Examination>
Physical examination revealed a thin but well-developed man in
acute distress. Heart rate was 92 bpm, temperature was 36.7 ℃,
blood pressure was 126/76 mmHg. There was no jaundice. Auscultation
of the abdomen showed hyperactive bowel sounds. Tympanic
sounds on percussion and local tenderness mostly
periumbilically was noted. There was no shifting dullness or
hepatosplenomegaly.
<Laboratory and Image
Study>
1.CBC/DC
|
WBC |
RBC |
MCV |
MCHC |
Hb |
Hct |
PLT |
|
K/μL |
M/μL |
fL |
g/dL |
g/dL |
% |
K/μL |
|
6.2 |
4.33 |
85.6 |
36.7 |
12.4 |
37.6 |
191 |
|
Seg |
Mono |
Eos |
Baso |
Lym |
|
% |
% |
% |
% |
% |
|
73.4 |
14 |
10 |
0 |
2 |
2. Biochemistry
|
BUN |
Cr |
Na |
K |
AST |
ALT |
Glu |
CRP |
|
mg/dL |
mg/dL |
meq/L |
meq/L |
U/l |
U/l |
mg/dL |
mg/dL |
|
13 |
1.1 |
135 |
4.4 |
28 |
17 |
107 |
0.46 |
3. Urine analysis: clear urine
|
Appearance |
Sp.gr |
PH |
Protein |
Glu |
Ketone |
|
Clear |
1.006 |
6.0 |
-- |
-- |
-- |
|
OB |
Uroblilinogen
(EU/dL) |
WBC
(/HPF) |
RBC
(/HPF) |
Cast
(/LPF) |
Crysal
(/LPF) |
|
-- |
0.1 |
1-2 |
1-2 |
-- |
-- |
4. Urine analysis: Dard brown
urine
|
Appearance |
Sp.gr |
PH |
Protein |
Glu |
Ketone |
|
Clear |
1.007 |
6.5 |
-- |
-- |
-- |
|
OB |
Uroblilinogen
(EU/dL) |
WBC
(/HPF) |
RBC
(/HPF) |
Cast
(/LPF) |
Crysal
(/LPF) |
|
-- |
0.1 |
1-2 |
1-2 |
-- |
--
|
Stool occult blood: normal.
The abdominal plain film
and CT study were normal.
<Course
and Treatment>
The patient developed symmetric
proximal muscle numbness and weakness in the four limbs and
progressed to paralysis within one week after admission. The
CSF, NCV and immunological examinations were all normal. He
was diagnosed with Guillain-Barre syndrome but plasmapheresis
cannot relieve his symptoms. Meanwhile, urinary discoloration
from yellowish to dark brown was noted 30 minutes after
standing at room temperature (Fig.1_A)
(Fig.1_B)
. Based on the urinary color change, acute
intermittent porphyria (AIP) with porphyric polyneuropathy was
diagnosed and confirmed by positive urine porphyrin and
porphobilinogen test. The activity of erythrocyte
porphobilinogen deaminase was 19.7 nmol/hr/ml RBC (normal
range: 30.3-73.7 nmol/hr/ml RBC) which was decreased
significantly as compared with normal. The patient was treated
with IV infusion of glucose water, Normosang (Heme arginate)
3mg/Kg/day for 4 consecutive days and adequate analgesics. He
was discharged one month later with complete resolution of
abdominal symptoms, but incomplete neurologic recovery.
<Analysis>
Porphyria is an inherited or acquired disorders resulting
from partial deficiencies in specific enzymes of heme
synthesis. This defect leads to overproduction and
accumulation of the porphyrin and/or their precursors. The
porphyria was classified into 2 major type, hepatic porphyria
and erythropoietic porphyria. The acute hepatic porphyries are
characterized by the rapid onset of neurologic manifestations.
In the erythropoietic porphyrias, porphyrins from bone marrow
erythrocytes and plasma are deposited in the skin and lead to
cutaneous photosensitivity.
This case was diagnosed as AIP, the most common form of
acute porphyria. It results from a deficiency of the enzyme
hydroxymethylbilane synthase. The predisposing factors include
porphyrinogenic drugs, alcohol ingestion, smoking, endogenous
and exogenous sex steroids, menstrual cycle, pregnancy,
low-calorie diet or starvation, stress and infection. The
typical presentations are abdominal pain, dark urine,
peripheral motor/sensory neuropathy, nausea/vomiting, mental
changes, convulsion, coma etc.
The definite diagnosis depends on excess plasma and urine
level of ALA (δ-aminolevulinic acid), PBG (porphobilinogen).
Decreased activity of PBG deaminase in erythrocyte was also
used to diagnose AIP. This patient’s neurologic presentation
was first diagnosed as Guillain-Barre syndrome, in fact it was
porphyric polyneuropathy. It is due to axonal degeneration and
primarily affects motor neurons. Motor neuropathy affects the
proximal muscles initially, more often in the shoulders and
arms. Progressive muscle weakness can lead to respiratory and
bulbar paralysis and even death.
<Reference>
- Adams & Victor's Principles of Neurology 16th ed,2002
- Sleisenger & Fordtran's Gastrointestinal and liver disease 6th ed. 2000
- Helen Thadani et al. BMJ 2000;320:1647-1651
- Harrison’s Principles of Internal Medicine 15th ed. 2001
- Bernard: Seminars in Liver Disease 18(1), 1998
- Raili Kauppinen et al: Medicine 71(1), 1992
- Yves Nordmann et al. Journal of Hepatology 1999;30:12-16
- Arch Intern Med 1993; 153: 2004-2008
- J.I. Suarez et al. Neurology 1997;
48:1678-1683
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Case Discussion
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