Page 196 Guide to Pain Management in Low-Resource Settings

184 Maged El-Ansary

PHN, but there are no evidence-based studies to prove • Headaches (present as a general response to viremia)
this point. • Appearance of red skin areas (2–3 days later)
• Th e patient cannot tolerate his clothes due to hy-
Diagnosis persensitivity of the skin (which may be misdiag-
nosed as urticaria with histamine release)
Which other conditions must be considered • Typical painful vesicles (blisters) will appear that
when herpes zoster is diagnosed? are full of serous fl uid (3–5 days later)

When taking the medical history, the patient’s age, sex, • Blisters full of pus will break down and start to
and race and certain psychosocial factors will guide you crust over (2–3 weeks later)
to the proper diagnosis. Diff erent age groups would in- • Th e crusts will heal and itching stops, but pain
dicate certain probable causes. One should be aware of persists along the distribution of the nerve (after
other possible causes, which may be present depending another 3–4 weeks)
on the age group. In rare cases the above symptoms will be ac-
companied by muscle weakness or paralysis if the
Age Possible Cause nerves involved also control muscle movement.
0–18 years AIDS/HIV, leukemia, Hodgkin’s disease, tubercu-
losis What are the most common nerves aff ected by
20–40 Steroid therapy, AIDS/HIV, diabetes mellitus, major herpes zoster?
years operations (organ transplant), infection (viral, bac- Trigeminal nerve
terial, fungal, or parasitic)
60–80 Malignant conditions should be the fi rst possibility, Trigeminal neuralgia (all three branches, ophthalmic
years and most of the above-mentioned factors could also branch infection: a dendritic ulcer of the cornea may
be present
develop as a serious complication, possibly causing cor-
neal opacity).
Sex
Cranial nerve VII
Males and females can develop herpes zoster.
With severe tinnitus, the patient complains about hear-
Race ing loud bells or humming in the head, which may drive
some patients to suicide.
Races with darker skin (Indian, African, and Latin
American) are more resistant than those with lighter Glossopharyngeal nerve
skin (Caucasian). Th e reason is unknown. Neuralgia with pain in the throat that increases with
swallowing.
Social and psychological factors
Intercostal nerves
Th e incidence of shingles is associated with exposure to
severe stressful conditions such as war, loss of a job, or Pain starting at the back of the chest wall and shooting
along the distribution of the corresponding intercostal
the death of close family members.
nerve, producing a feeling of chest tightness and possi-
What symptoms are helpful in diagnosis of bly, if left-sided, confused with myocardial infarction.
shingles and postherpetic neuralgia?
Lumbar and sacral plexuses and nerves
Th e clinician should know the symptoms of acute her-
Pain in the genital tract (in males and females) may be
pes zoster and the diff erent stages of disease, which typ-
confused with the diagnosis of genital herpes simplex.
ically are:
However, the fact that PHN is more painful and not
• Sharp and jabbing, burning, or deep and aching
usually recurrent like simplex virus should lead to the
pain
right diagnosis.
• Extreme sensitivity to touch and temperature
changes (symptoms 1 and 2 could be misdiag- What observations are typically made
nosed as myositis, pleurisy, or ischemic heart dis- in the examination of the patient?
ease) Observed signs:
• Itching and numbness (which may be misdiag- • Th e skin is discolored, with areas of hyper- and
nosed as skin allergy) hypopigmentation called “café au lait” skin.