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Systemic sclerosis (SSc) is a chronic multisystem disease
characterized by microangiopathy, fibrosis of the skin and internal organs, and
autoimmune disturbances. Although  it is
a chronic disease, scleroderma can present to emergency with symptoms unless
treated aggressively can result in death of the patient.

 

RENAL EMERGENCIES

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ACUTE SCLERODERMA RENAL CRISIS (SRC )

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

·        
 Acute onset of renal
failure

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

·        
A urine sediment that is usually normal or reveals only 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)

Approximately 80% of the renal crisis occur
in patients with diffuse cutaneous systemic sclerosis within the first 4-5
years of disease. Other risk factors include high dose steroids and  presence of anti-RNA polymerase III antibody.

Treatment

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

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

The improvement in renal function can continue for up to 2
years. Allograft survival is lower compared with that of transplant recipients
without scleroderma.

Differential Diagnosis

Thrombotic
thrombocytopenic purpura (TTP), is a rare but potentially lethal condition. 5
The diagnosis is made clinically and is classically characterized 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, will be normal in SRC and  ADAMTS13 level will be  extremely low in TTP. 

Cardiopulmonary causes

The heart is one
of the major organs involved in scleroderma. Cardiac involvement 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 with minimal or no pulmonary fibrosis is a severe complication, and is
the result of narrowing of small pulmonary arteries.

Clinical signs
of PAH include dyspnea on exertion, fatigue, chest pain, dizziness,
palpitations, and edema at the lower extremities. On examination, a loud
pulmonary component of the second heart sound, gallop, and pansystolic murmur
of tricuspid regurgitation may be found, along with features of right heart
failure in advanced cases7.

Chest X-ray and
electrocardiogram may reveal signs suggestive of PAH, mainly in the later
stages, such as an enlarged pulmonary artery, attenuation of peripheral
pulmonary vascular markings (at the chest X-ray), and peaked P wave ? 2.5 mm in
leads II, III and Avf7,8. If PAH is suspected, a transthoracic
Doppler echocardiography is recommended.7,8 On echocardiography, PAH
is defined as mean PAP > 25 mmHg at rest, > 30 mmHg during exercise, or
systolic pulmonary pressure > 40 mmHg. Clues to diagnosis of PAH can be an
elevated tricuspid regurgitation velocity  jet above 2.8 m/s, or a dilated right
ventricle or  atrium9. Reduced
carbon monoxide diffusing capacity is a marker of pulmonary vascular disease
and is standardly used in the diagnostic approach when PAH is suspected. Of
note, it is associated with poor prognosis.

Before starting
the treatment,all patients  suspected to
have PAH after noninvasive evaluation should undergo right heart catheterization.
This method is the gold standard for diagnosing PAH, and allows for the
measurement of the transpulmonary gradient (PAP mean wedge).It  was found to be significantly elevated only in
PAH patients, but not in patients whose pulmonary hypertension was due to
increased cardiac output, left heart myocardial or valvular disease8,10.
A more reliable diagnostic parameter for PAH is pulmonary vascular resistance ,
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 valve
disease or left ventricular heart disease26. Consequently, PAH is a
diagnosis of exclusion. In the absence of lung disease, thromboembolism, left
ventricular or valve pathology, the diagnosis of PAH requires both a mean PAP
greater than 25 mmHg and a PVR greater than 3 Wood units with a pulmonary
capillary wedge pressure < 15 mmHg (after exclusion of left heart disease)8,10. TREATMENT SSc-associated PAH historically had a poor prognosis with a one-year survival rate of 45%. Survival, though still poor, has significantly increased with modern therapies such as prostanoids, endothelin receptor antagonists, and phosphodiesterase-5 inhibitors. Drugs used in PAH 1) Prostanoids a)Epoprostenol:    Starting dose of infusion is 1-2 ng/kg per minute, gradually increased up to 25-40 ng/kg per minute b) Treprostinil: given as a continuous subcutaneous or intravenous infusion in patients with PAH from functional class II, III and IV Dose:1.25  ng/kg per minute 2).Endothelin receptor antagonists a)Bosentan: It is indicated for PAH functional classes II, III and IV. Dose: 62.5 mg bid for 4 weeks before titration up to 125-250 mg bid b) Ambrisentan: Dose: 2.5-10 mg Ambrisentan in combination with tadalafil reduces the risks of disease progression and hospitalization for worsening PAH and improves exercise ability.   3)PDE inhibitors a)    Sildenafil: Dose:20mg  tid b)    Tadalafil: Dose:40mg OD CORONARY VASCULATURE AND MYOCARDIAL PERFUSION The hyperactivation of the immune system and systemic inflammation lead to premature atherosclerosis and earlier occurrence of its clinical manifestations.  Myocardial infarction has been described in SSc patients with unaltered coronary arteries. Vasospasm of the small coronary arteries and arterioles (the so-called myocardial Raynaud's phenomenon) is considered to be involved in the early scleroderma-related ischemic myocardial changes with subsequent ischemia reperfusion injury and the development of structural vascular alterations.  PERICARDIAL DISEASE Asymptomatic pericardial effusions commonly occur in scleroderma11. Moreover, there also have been large effusions causing tamponade and can even occur prior to skin thickening and the diagnosis of scleroderma12,13. Pericardial effusions are also frequently associated with pulmonary hypertension and may be the presenting feature of pulmonary hypertension in scleroderma14. TREATMENT  Treatment may include NSAIDs. Corticosteroids are considered to be of limited benefit.Immunosuppressors may be indicated if profound inflammation is evident. Pericardiocentesis is indicated in cases of life-threatening tamponade. CONDUCTION SYSTEM DISEASE Arrhythmias and conduction abnormalities are thought to be a result from conduction system fibrosis15,16 and myocardial fibrosis17. Supraventricular arrhythmias are considered to be more common in SSc patients, occurring in approximately two thirds of  cases18.  Holter monitoring is therefore recommended in patients with symptoms of palpitations, light headedness, dizziness, or syncope. TREATMENT AICD implantation is recommended in patients with inducible ventricular tachycardia or reduced LVEF. INTERSTITIAL LUNG DISEASE In scleroderma, end stage lung disease secondary to ILD, accounts for more than 50% of SSc-related deaths 19.  HRCT is the standard method for the noninvasive diagnosis of SSc-ILD.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 with other PFT abnormalities 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 halts the progression of ILD.26,27,28Once the patient reached ESLD, pulmonary rehabilitation and lung transplantation are the treatments which can  be offered.  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 from the SSc disease process or because of  atheromatous disease.Possibility of proximal vessel disease should always be considered in patients who have SSc and 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 antiphospholipid syndrome, which is rare 35. Permanent discolouration of the digit and increased pain are the main symptoms of critical ischemia.If any evidence of critical ischemia is seen, the distal pulses must be checked.Absence of one or more peripheral pulses suggests a proximal vessel problem, which demands further investigation.   INVESTIGATIONS 1)    Doppler ultrasound If the peripheral pulses are difficult to feel, then Doppler ultrasound will establish whether significant large vessel disease is likely requiring  angiography.  2)X ray A plain radiograph of the affected digit may 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 RP. 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.37This drug acts very rapidly and helps in ulcer healing by improving the microcirculation. 5)Botulinum toxin  Botulinum toxin 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 infected or necrotic tissue. But once 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 under gastroendoscopy observation is unique known as "watermelon stomach". GAVE can precede an 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 severe GI bleeding, although achlorhydria, pernicious anemia is more common. Treatment Bipolar cautery, heat probe, sclerotherapy and laser ablation 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 compromised 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 major 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 the upright 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 resulting from excessive collagen deposition. Treatment The initial treatment for this condition should include bowel rest, intravenous fluid infusion and electrolyte correction. Octreotide has also been shown to be effective.43 Neostigmine can lead to prompt colon decompression. If octreotide and neostigmine treatments are not effective, however, colonoscopic decompression is normally 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.

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