Systemic are of value even in normotensive renal crisis.Continuation

Systemic sclerosis (SSc) is  described by microangiopathy,fibrosis of  skin and internal organs and autoimmune disturbances.
Though  scleroderma is a chronic systemic
illness, it can present to emergency with symptoms, unless treated aggressively
can be life threatening.

 

RENAL EMERGENCIES

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ACUTE SCLERODERMA RENAL CRISIS (SRC )

Scleroderma renal crisis develops in approximately
10% – 15% of patients.(1)It  is described by:

·        
 Acute onset of renal
failure

·        
Sudden onset of moderate to marked hypertension (some patients
remain normotensive)(2)

·        
A urine sediment that is usually normal or occasionally reveals mild
proteinuria with few cells or casts

SRC  is
also characterized by microangiopathic haemolytic anemia and thrombocytopenia.
Congestive heart failure and pericardial effusions are common.(3)

Around  80% of renal crisis occur in patients with
diffuse  systemic sclerosis within the  4-5 years of disease. Presence of anti-RNA
polymerase III antibody and recent use of high dose of steroids are other risk
factors.

Treatment

 ACE inhibitors is the treatment of choice for
scleroderma renal crisis.ACE inhibitors are of value even in normotensive renal
crisis.Continuation of ACE inhibitors in patients on dialytic support often
leads to enough renal recovery to permit dialysis discontinuation after 6-18
months.

If treatment is started before marked irreversible vascular
injury has occurred,control of hypertension can stabilize or even improve renal
function in  55% to 70% of cases.(3)
Nevertheless, the mortality is high and a poor outcome is common.(4) Patients
who fail to respond to ACE inhibitor may  respond to potent vasodilators such as
minoxidil along with beta blockers and diuretics. Patients with
severe scleroderma renal crisis may have myocarditis and ventricular stiffness.
So,maintenance of blood volume is essential.

The  renal function can
continue to improve  for up to 2 years.
Allograft survival is lower compared to  transplant recipients without scleroderma.

Differential Diagnosis

Thrombotic
thrombocytopenic purpura (TTP), is a rare but potentially fatal condition. 5
The diagnosis is made clinically and is classically described by a pentad of
thrombocytopenia, microangiopathic hemolytic anemia, transient neurological
symptoms, renal dysfunction, and fever.Basic pathogenesis is presence of large
von Willebrand factor(vWF) multimers 
ascribed to deficiency of the vWF-cleaving protease (ADAMTS13) enzyme 6.The vWF cleaving protease done by
activity-based assay, is  normal in SRC
and  ADAMTS13 level is    low
in TTP. 

Cardiopulmonary causes

 One of the main organs involved in scleroderma
is the heart. Involvement of the heart can generally be divided into
direct myocardial effects and the indirect effect of other organ involvement .
Direct myocardial disease includes myocarditis, cardiac failure, cardiac
fibrosis, coronary artery disease, conduction system abnormalities, and pericardial
disease.

 

RIGHT HEART FAILURE AND PAH

Right heart
failure is most commonly the result of pulmonary hypertension. Pulmonary
hypertension is a common manifestation of scleroderma and a poor prognostic
sign.

PAH  results from restricted flow through the
pulmonary arterial circulation leading to increased pulmonary vascular
resistance and right heart failure.

PAH in the
context of pulmonary fibrosis is  of
moderate degree and has  slow
progression.PAH occurs due to increase in resistance in pulmonary vasculature.PAH
in SSc patients in the absence of pulmonary fibrosis is a severe complication,
and it  results from narrowing of small
pulmonary arteries.

Patients with PAH
can have dyspnea on exertion, fatigue, chest pain, giddiness, palpitations, and
pedal edema. On examination, a loud pulmonary component of the second heart
sound, gallop, and pan-systolic murmur of tricuspid regurgitation may be found,
along with signs of right heart failure in advanced cases7.

Chest X-ray
shows an enlarged pulmonary artery and ECG may show peaked P wave ? 2.5 mm in
leads II, III and Avf7,8.  Doppler echocardiography is suggested if PAH
is suspected.7,8 PAH is defined as mean PAP > 25 mmHg at rest,
> 30 mmHg during exercise, or systolic pulmonary pressure > 40 mmHg on echocardiography.
Clues to diagnosis of PAH could be an increased TR velocity  jet > 2.8 m/s, or a dilated right ventricle
or  atrium9. Carbon monoxide
diffusing capacity(DLC0) is also used in the diagnosis when PAH is suspected
and reduced DLCO is a marker of pulmonary vascular disease . Of note, it is
associated with poor prognosis.

Before starting
the treatment,all patients  suspected to
have PAH after noninvasive evaluation should be evaluated with  right heart catheterization. It is the gold
standard to diagnose  PAH, and helps in measurement
of the transpulmonary gradient (PAP mean wedge).It  was  significantly elevated only in PAH patients
and  not in patients whose pulmonary
hypertension was due to increased cardiac output, left heart myocardial or valvular
disease8,10.Pulmonary vascular resistence is a more  reliable diagnostic parameter for PAH  , which reflects the influence of
transpulmonary gradient and cardiac output and is only elevated if the vascular
obstruction occurs within the precapillary pulmonary circulation. However, PVR
can also be elevated in patients with left ventricular heart disease or valve
disease 26. However, PAH is a diagnosis of exclusion. In the absence
of thromboembolism,lung disease, valve or left ventricular  pathology, the diagnosis of PAH requires both
a mean PAP > 25 mmHg and a PVR > 3 Wood units with a pulmonary capillary
wedge pressure 50% of SSc-related deaths 19.

 The standard method for the noninvasive
diagnosis of SSc-ILD is HRCT.The HRCT pattern seen in SSc patients is generally nonspecific
interstitial pneumonia 20, with a greater proportion of ground-glass
opacities and a lower degree of coarse reticulation . However, a usual
interstitial pneumonia pattern can also be seen . Reversibility of HRCT changes
is rare 21. 

Pulmonary function
tests

 Dl,CO is reduced in almost all
patients  22 and correlates
with the extent of lung disease on HRCT 23.  Although FVC
and Dl,CO are both identified as
adverse prognostic markers 24,25, a declining Dl,CO is the single most significant marker of poor outcome
10.

TREATMENT

Mycophenolate
mofetil,cyclophosphamide and rituximab if used in appropriate doses stops the
progression of ILD.26,27,28Once patient reaches ESLD, pulmonary
rehabilitation and lung transplantation are the treatment options.

 IMPENDING GANGRENE

Peripheral vascular involvement occurs in
almost all patients who have systemic sclerosis (SSc).Digital
ischemia can result in digital ulcers, digital pitting 29, and
sometimes gangrene.

Digital ischemia in SSc can be
so severe due to abnormalities of neuroendothelial control mechanism,
structural abnormalities of the microvasculature  and intravascular factors, including a
procoagulant tendency and oxidative stress 30.

SSc has been suggested to be
primarily a vascular disease31.32.

If macrovascular disease is increased in
SSc, it may be due to atheromatous disease or from the disease process itself.Possibility
of proximal vessel disease should always be considered in  SSc patients with  severe digital ischemia.

 

DIAGNOSIS

Although the main contributor
to disease pathogenesis is a noninflammatory microangiopathy in most patients
who have SSc-related peripheral vascular disease, other possibilities should
always be considered,such as

 (1) concomitant proximal vessel disease

 (2) vasculitis, which is unusual in SSc 33,34

 (3) thrombotic disease as part of a
concomitant APS, which is rare 35.Prolonged discolouration of the digit and increased
pain are the main symptoms of critical ischemia.Peripheral pulses must be
checked if any evidence of critical ischemia is seen.Absence of one or more peripheral pulses suggests a proximal vessel
problem, which demands more investigation.

 

INVESTIGATIONS

1)    Doppler ultrasound

If the distal pulses are
difficult to feel, then Doppler ultrasound will establish whether significant
large vessel disease is likely which requires angiography.

 2)X ray

A plain radiograph of the
affected digit  will show underlying
calcinosis  or osteomyelitis.

4)Nailfold capillaroscopy assess
microvascular structure.

 5)
Thermography  gives an indirect
assessment of small and large vessel function.

6) Conventional  MRI and CT angiography   assess
large vessel structure.

 

MANAGEMENT

General
Measures

Avoidance
of cold,stress, nicotine, caffeine, and sympathomimetic decongestants are  nonpharmacologic elements to prevent or avoid
exacerbating Raynaud’s phenomenon. Cigarette smoking is a risk factor for
severity of digital ischaemia. 36

 

1)Calcium channel blockers

They are  considered first-line treatment in SSc-related
Raynaud’s phenomenon.

Treatment with  slow release nifedipine (30-180mg daily) may
decrease the frequency or severity of attacks.

2)Phosphodiesterase type 5 inhibitors

Sildenafil and tadalafil has been proven
to be effective in RCTs in preventing new onset ulcers and healing the existing
ulcers. 

3)Endothelin-1 receptor
antagonists

Bosentan is also found effective in
preventing new onset ulcers in patients with scleroderma.

4)Prostacyclin
analogs: 

Iloprost (carbaprostacyclin,
given parenterally at 0.5-2 ng/kg/minute), is a potent vasodilator.37It acts very rapidly and helps in healing
ulcers by improving the microcirculation.

5)Botulinum toxin

 It has been shown to improve digital perfusion in
patients with resistant Raynaud’s phenomenon.  

6)Surgery

The most common form of surgery is
debridement of necrotic or infected tissue.But if osteomyelitis is established,
amputation may be necessary.

If patients have proximal arterial
disease, angioplasty may be indicated. Finally, if an area of calcinosis is
underlying a nonhealing ulcer, it has to be  debulked.

7)Lumbar sympathectomy

A temporary sympathetic block
could be considered if patients remain in severe pain.38

 

 

 

GI
COMPLICATIONS

 

GAVE(Gastric
Antral Vascular Ectasia):

Mucosal telangiectasias are the most common
source of bleeding.

The appearance of GAVE in
gastroendoscopy is uniqueand is  known as
“watermelon stomach”. GAVE can precede  SSc diagnosis.39 It is estimated
that the prevalence of GAVE ranges from 5.7% to 14% of SSc patients.40,41
GAVE can sometimes manifest itself as GI bleeding, although pernicious anemia,
achlorhydria is more common.

Treatment

Sclerotherapy,bipolar cautery,laser ablation and heat probe are
available for the treatment of GAVE.

SMALL
BOWEL

The small intestine is the second most commonly
involved portion of GI tract during SSc, following the esophagus. Small intestine
function is impaired in 40% of SSc patients.42 Small intestine
hypomotility is the primary abnormality and may lead to pseudo-obstruction and
bacterial overgrowth, which is the main cause of malnutrition in SSc patients.
Additionally, pneumatosis cystoides intestinalis (PCI) may occur but is a rare
condition.

Small intestine pseudo-obstruction: 

 Small
intestinal hypomotility because may provoke luminal dilatation and overt
pseudo-obstructions.Radiological evidence of distended bowel loops and
air-fluid levels in erect position is an important diagnostic marker of this
pathological condition. Acute episodes can last only a few hours, but in the
most severe cases intestinal loops are chronically distended and air-fluid
levels are invariably detected.

A more characteristic sign is a ‘hide-bound’  appearance produced by closely packed valvulae
due to excessive collagen deposition.

Treatment

The initial treatment  should include bowel rest, intravenous fluid
infusion and electrolyte correction.

Octreotide has also been shown to be effective.43
Neostigmine can lead to rapid colon decompression.

If neostigmine and octreotide treatments are not effective,then
colonoscopic decompression is  the
treatment of choice.

Pneumocystis cystoides intestinalis

 Primary pneumatosis
intestinalis is a benign idiopathic condition in which multiple thin-walled
cysts develop in the submucosa or subserosa of the colon. Usually, this form
has no associated symptoms, and the cysts may be found incidentally through
radiography or endoscopy.

Pneumatosis
intestinalis may be complicated by pneumoperitoneum.Generally,
the prognosis of PCI is good.