Deep vein thrombosis

The onset of DVT may be silent or heralded by pain in the
calf, often about 10 days after immobilization for
surgery, parturition or an infection. The leg becomes
swollen and cyanotic distal to the thrombus. The calf
may hurt when handled or if the foot is dorsiflexed
(Homans sign). Sometimes a pulmonary embolus is
the first sign of a silent deep vein thrombosis.
Suitable investigations include venography, Doppler
ultrasonography, which can only detect thrombi in
large veins at, or above, the popliteal fossa, and
I-fibrinogen isotope leg scanning.
Treatment is anticoagulation with heparin and
later with a coumarin. The value of thrombolytic
regimens has yet to be assessed properly. Prevention
is important. Deep vein thrombosis after a surgical
operation is less frequent now, with early postoperat-
ive mobilization, regular leg exercises, the use of elastic
stockings over the operative period and prophylaxis
with low dose heparin.

Treatment of Chronic Eczema

This responds best to steroids in an ointment base, but
is also often helped by non-steroid applications such
as ichthammol and zinc cream or paste.
The strength of the steroid is important.
Nothing stronger than 0.5 or 1% hydrocortisone
ointment should be used on the face or in infancy.
Even in adults one should be reluctant to prescribe
more than 200g/week of a mildly potent steroid,
50g/week of a moderately potent or 30g/week of a
potent one for long periods. Very potent topical
steroids should not be used long-term.
Bacterial superinfection may need systemic antibi-
otics but can often be controlled by the incorporation
of antibiotics, e.g. fusidic acid, mupirocin, neomycin
or chlortetracycline, or antiseptics, e.g. Vioform, into
the steroid formulation. Many proprietary mixtures
of this type are available in the UK. Chronic localized
hyperkeratotic eczema of the palms or soles can be
helped by salicylic acid (16% in emulsifying oint-
ment) or stabilized urea preparations.

G6PD Deficiency

G6PD deficiency is an inherited disorder of the red blood cell, inherited in an x-linked
recessive manner – males are affected while the females are carriers. G6PD is an enzyme
essential in keeping glutathione in the reduced state that in turn is vital to maintain the
integrity of the red cell membrane. In G6PD deficiency the red blood cells are prone to
haemolysis when exposed to oxidants or when certain foods or herbs are ingested. A list
of drugs and herbs that can precipitate haemolysis is provided in the appendix (Luzzato,
1992).

The incidence of G6PD deficiency varies among the various ethnic groups as follows -
Chinese 3.1%, Malay 1.4%, and Indian 0.2% (Robinson et al., 1976). These results were
obtained by using a fluorescent screening method, that had been found to be as sensitive
and specific as other screening tests (Fairbanks & Fernandez 1969).