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{{Hemosiderosis }}
{{Hemosiderosis }}  
{{CMG}}
{{CMG}}[[Roghayeh Marandi]]
==Overview==
==Overview==
[[Hemosiderosis]] is a condition whenever there is an [[Iron overload|overload of iron]] which results in the [[Deposition (chemistry)|deposition]] of [[hemosiderin]] in many [[organs]] and [[tissues]]. [[Hemosiderosis]] occurs in the setting of [[genetic]] disorders (ie [[hemochromatosis]] occurs due to excessive [[iron]] [[absorption]]), [[Transfusional iron overload|transfusional]], abnormal [[clearance]]/use, increase [[absorption]], abnormal [[hepcidin]], [[hemolytic anemia]], or homeotropic [[parasites]]. Although [[hemosiderosis]] implies [[iron overload]] without tissue damage, often an early stage of [[iron]] accumulation, there are three  types of [[hemosiderosis]]: [[Transfusion hemosiderosis]], [[Idiopathic pulmonary hemosiderosis]], [[Transfusional diabetes]]. [[Idiopathic pulmonary hemosiderosis]] ([[IPH]]) is a rare disease of unknown [[etiology]] characterized by repeated episodes of a diffuse [[alveolar]] [[hemorrhage]] which cause periodic attack of [[tachycardia]], [[pyrexia]], [[pallor]], [[fatigue]], [[cyanosis]], increasing [[dyspnea]], signs of [[congestive cardiac failure]], severe [[anamia]] and [[hemoptysis]]. Repeated alveolar hemorrhage causes the accumulation of
[[Idiopathic pulmonary hemosiderosis]] ([[IPH]]) is a rare disease of unknown [[etiology]] characterized by repeated episodes of a diffuse [[alveolar]] [[hemorrhage]] which cause periodic attack of [[tachycardia]], [[pyrexia]], [[pallor]], [[fatigue]], [[cyanosis]], increasing [[dyspnea]], signs of [[congestive cardiac failure]], severe [[anamia]] and [[hemoptysis]]. The repeated alveolar hemorrhage causes the accumulation of [[hemosiderin]], a by-product of [[hemoglobin]] breakdown, in the alveoli. [[Alveolar]] [[macrophages]] take up these [[hemosiderin]] molecules, usually within 36 - 72 hours, and can remain in the [[lungs]] for up to 8 weeks. Between attacks, patients may remain well but commonly there is chronic ill-health. Over the time, It  can lead to multiple [[respiratory]] [[complications]] and permanent [[lung]] damage. It is not familial and is found primarily in children from a few months to 16 years of age and rarely be seen in adults.
hemosiderin, a by-product of hemoglobin breakdown, in the alveoli.Alveolar macrophages take up these hemosiderin molecules, usually within 36 - 72 hours, and can remain in the lungs for up to 8 weeks. Between attacks patient may remain well but commonly there is chronic ill-health. Over the time, It  can lead to multiple [[respiratory]] [[complications]] and permanent [[lung]] damage. It is not familial and is found primarily in children from a few months to 16 years of age and rarely be seen in adults.<ref name="pmid26692115">{{cite journal |vauthors=Chen XY, Sun JM, Huang XJ |title=Idiopathic pulmonary hemosiderosis in adults: review of cases reported in the latest 15 years |journal=Clin Respir J |volume=11 |issue=6 |pages=677–681 |date=November 2017 |pmid=26692115 |doi=10.1111/crj.12440 |url=}}</ref> <ref name="pmid18147236">{{cite journal |vauthors=McLETCHIE NG, COLPITTS G |title=Essential brown induration of the lungs; idiopathic pulmonary haemosiderosis |journal=Can Med Assoc J |volume=61 |issue=2 |pages=129–33 |date=August 1949 |pmid=18147236 |pmc=1591635 |doi= |url=}}</ref>


==Historical Perspective==
==Historical Perspective==
*[[IPH]] was first described as "brown lung induration" by Rudolf Virchow in 1864 in patients after their death.<ref name="pmid32491447">{{cite journal |vauthors=Madu A, Siddiqui AH |title= |journal= |volume= |issue= |pages= |date= |pmid=32491447 |doi= |url=}}</ref>
[[IPH]] was first described as "brown lung induration" by Rudolf Virchow in 1864 in patients after their death. Wilhelm Ceelen gave a more detailed description of the condition after [[autopsies]] revealed large amounts of [[hemosiderin]] in 2 children in 1931. In 1944, the antemortem [[diagnosis]] was made by Waldenstrom.
*The findings were first to the clinical symptoms by Wilhelm Ceelen gave a more detailed description of the condition after autopsies revealed large amounts of hemosiderin in 2 children in 1931.
*In 1944, the antemortem diagnosis was made by Waldenstrom


==Classification==
==Classification==
*[[IPH]] may be grouped  into three categories based on disease characteristic:
Based on the duration of symptoms, [[pulmonary hemosiderosis]] may be classified as either [[acute]] or [[chronic]] phase.[[Pulmonary hemosiderosis]] may be classified into three groups based on disease characteristic: first group with circulating [[Anti-GBM antibody|anti-glomerular basement membrane]] ([[Anti-GBM antibody|anti-GBM]]) antibodies, second group, with [[immune complex disease]], and the third group without known [[Immunological|immunologic]] association or ([[Idiopathic pulmonary hemosiderosis]]).
:*Group 1 pulmonary hemosiderosis involves PH with circulating anti-GMB antibodies.
:*Group 2 pulmonary hemosiderosis involves PH with an immune complex disease such as systemic lupus erythematosus, SLE.
:*Group 3 pulmonary hemosiderosis involves no demonstrable immune system involvement.


==Pathophysiology==
==Pathophysiology==
*Recurrent episodes of intra-alveolar hemorrhage attract macrophages to the alveoli, which digest the hemosiderin (iron component) found in hemoglobin, leading to an abnormal accumulation of hemosiderin-laden macrophages. This attracts more pro-inflammatory cytokines and causes chronic inflammation and thickening of the alveolar basement membrane. Ultimately this causes interstitial lung fibrosis with a restrictive picture on spirometry.  
After the repeated episodes of a diffuse [[alveolar]] [[hemorrhage]], the [[alveolar|alveolar macrophages]] are responsible for the repeated clean up of excess [[blood]]. As the [[macrophages]] degrade the [[erythrocytes]], the excess [[iron]] from [[heme]] [[degradation]] within the [[alveolar]] [[macrophages]] stimulates [[intracellular]] [[ferritin]] [[molecules]]. Further processing of the [[ferritin]] leads to [[hemosiderin]] complexes.(see below for more information). In the early stages of [[pulmonary hemosiderosis]], [[interstitial]] and intra-alveolar [[hemorrhage]] predominate, with collections of both free [[hemosiderin]] and [[hemosiderin]]-filled [[macrophages]] found in the [[Alveolar|alveolar space]]s and the [[interstitium]]. When the [[disease]] progresses, [[interstitial fibrosis]] ensues. Pulmonary hemosiderosis can occur either as a [[primary]] lung disorder ([[Idiopathic pulmonary hemosiderosis]]) or as the [[sequela]] to other [[pulmonary]], [[cardiovascular]], or [[immune system disorder]].
*In infants, the disease is poorly understood.
 
<ref name="pmid27644948">{{cite journal |vauthors=Castellazzi L, Patria MF, Frati G, Esposito AA, Esposito S |title=Idiopathic pulmonary haemosiderosis in paediatric patients: how to make an early diagnosis |journal=Ital J Pediatr |volume=42 |issue=1 |pages=86 |date=September 2016 |pmid=27644948 |pmc=5029079 |doi=10.1186/s13052-016-0296-x |url=}}</ref><ref name="pmid20442117">{{cite journal |vauthors=Lara AR, Schwarz MI |title=Diffuse alveolar hemorrhage |journal=Chest |volume=137 |issue=5 |pages=1164–71 |date=May 2010 |pmid=20442117 |doi=10.1378/chest.08-2084 |url=}}</ref><ref name="pmid24125570">{{cite journal |vauthors=Taytard J, Nathan N, de Blic J, Fayon M, Epaud R, Deschildre A, Troussier F, Lubrano M, Chiron R, Reix P, Cros P, Mahloul M, Michon D, Clement A, Corvol H |title=New insights into pediatric idiopathic pulmonary hemosiderosis: the French RespiRare(®) cohort |journal=Orphanet J Rare Dis |volume=8 |issue= |pages=161 |date=October 2013 |pmid=24125570 |pmc=3852822 |doi=10.1186/1750-1172-8-161 |url=}}</ref><ref name="pmid30125478">{{cite journal |vauthors=Welsh SK, Casey AM, Fishman MP |title=Pulmonary hemorrhage in infancy: A 10-year single-center experience |journal=Pediatr. Pulmonol. |volume=53 |issue=11 |pages=1559–1564 |date=November 2018 |pmid=30125478 |doi=10.1002/ppul.24142 |url=}}</ref>


==Causes==
==Causes==
* There are no established causes for IPH, but it is likely to be multifactorial. Some consider it to be an autoimmune condition. The evidence is backed by the fact that the disease responds to immunosuppressants.  
There are no established causes for [[idiopathic pulmonary hemosiderosis]], but it is likely to be multifactorial. Some consider it to be an [[autoimmune]] condition. The evidence is backed by the fact that the disease responds to [[immunosuppressants]]. Other [[hypotheses]] for this condition include [[allergy]], due to this frequent association with Cow's milk protein [[allergy]], or [[genetic]] cause, due to the rare finding of familial clustering (but without any identified [[genes]] yet), and [[environmental]] factors such as its association with the [[fungi]] (Stachybotrys atra) [[exposure]], or [[toxic]] [[insecticides]] (based on epidemiological studies in rural Greece), and [[Preterm birth|premature birth]].
*Other hypotheses for the pathophysiology of the condition include allergy, due to its frequent association with Cow's milk protein allergy, genetic, due to the rare finding of familial clustering (but without any identified genes yet), and environmental due to the now refuted claim of its association with the fungi Stachybotrys atra exposure, toxic insecticides (based on epidemiological studies in rural Greece), premature birth.


==Differentiating IPH from other Diseases==
==Differentiating IPH from other Diseases==
* [[IPH]] must be differentiated from other diseases that cause alveolar hemorrhage,  such as those include infectious etiologies( ARDS, streptococcus pneumoniae, staphylococcus aureus, and legionella, influenza A and pneumocystis jirovecii), rheumatic disease such as systemic lupus erythematosus, antiphospholipid antibody syndrome, Goodpasture disease, microscopic, and granulomatous polyangiitis, and mixed cryoglobulinemias, drug-induced injury in medications such as medication such as amiodarone, nitrofurantoin, and infliximab. Penicillamine, thromboembolic disease, bleeding disorders, and neoplasms
[[Idiopathic pulmonary hemosiderosis]] must be differentiated from other diseases that cause [[alveolar]] [[hemorrhage]],  such as those include [[infectious]] [[etiologies]]( [[ARDS]], [[Streptococcus pneumonia]], [[Staphylococcus aureus]], and [[legionella]], [[influenza A]] and [[Pneumocystis jirovecii]]), [[rheumatic diseases]] such as [[systemic lupus erythematosus]], [[antiphospholipid antibody syndrome]], [[Goodpasture disease]], [[Microscopic polyangiitis|microscopic granulomatous polyangiitis]], and mixed [[Cryoglobulinemia|cryoglobulinemias]], [[drug-induced]] injury in [[medications]] such as [[amiodarone]], [[nitrofurantoin]], and [[infliximab]], [[Penicillamine]], or from [[thromboembolic disease]], [[bleeding disorders]], and [[neoplasms]].


==Epidemiology and Demographics==
==Epidemiology and Demographics==
* The prevalence and incidence of IPH are relatively unknown because of the rare nature.  
The [[prevalence]] and [[incidence]] of [[idiopathic pulmonary hemosiderosis]] are relatively unknown because of the rare nature. [[IPH]] is more commonly observed among children. 20% of cases are adult-onset [[IPH]].[[IPH]] affects males and females equally in childhood-onset [[IPH]]. [[Males]] are more commonly affected by [[IPH]] than [[females]] in adult-onset [[IPH]].
===Age===
*IPH is more commonly observed among children. ( approximately 80% of cases are seen in children who are diagnosed in the first decade of life.)
*205 of cases are adult-onset IPH.  
===Gender===
*IPH  affects males and females equally in childhood-onset IPH
*Adult-onset IPH are almost twice as many males as females.
*Males are more commonly affected with IPH than females in adult-onset IPH.
===Race===
*There is no racial predilection for IPH.


==Risk Factors==
==Risk Factors==
*There are no established risk factors for [[IPH]].
There are no established risk factors for [[Idipathic pulmonary hemosiderosis]].


== Natural History, Complications and Prognosis==
== Natural History, Complications and Prognosis==
*The clinical spectrum of IPH ranges from asymptomatic cases to a chronic cough and dyspnea to repetitive hemoptysis with fatigue, anemia, and slowly progressive dyspnea and life-threatening acute respiratory failure.  
The clinical spectrum of IPH ranges from [[asymptomatic]] cases to a chronic [[cough]] and [[dyspnea]] to repetitive [[hemoptysis]] with [[fatigue]], [[anemia]], and slowly progressive [[dyspnea]] and life-threatening acute [[respiratory failure]]. Common complications of [[IPH]] include [[Iron deficiency anemia]] and [[pulmonary fibrosis]]. [[Prognosis]] is generally variable, and the mean survival rate of patients with [[IPH]] is  2.5 to 5 years after diagnosis. Deaths can occur from acute massive [[hemorrhage]] or after progressive [[pulmonary insufficiency]] and [[right heart failure]].
*Common complications of IPH include Iron deficiency anemia and pulmonary fibrosis.  
*Prognosis is generally variable, and the mean survival rate of patients with IPH  is  2.5 to 5 years after diagnosis. Deaths can occur from acute massive hemorrhage or after progressive pulmonary insufficiency and right heart failure.


== Diagnosis ==
== Diagnosis ==
===Diagnostic Criteria===
There are no established criteria for the diagnosis of [[idiopathic pulmonary hemosiderosis]]. Lung [[biopsy]] is the gold standard for the diagnosis of [[IPH]], where the hemosiderin-laden macrophages can be visualized. However, it is an invasive procedure and is often not practicable in children.
*The diagnosis of acute IPH is made clinically, after other known causes of pulmonary and systemic or visceral hemorrhage have been excluded.
*Lung biopsy is the gold standard for the diagnosis of IPH, where the hemosiderin-laden macrophages can be visualized. However, it is an invasive procedure and is often not practicable in children.


=== Symptoms ===
=== History and Symptoms ===
The clinical features of idiopathic pulmonary hemorrhage depend on whether it is acute or chronic
The most common symptoms of [[IPH]] in the acute phase include severe [[dyspnea]], [[cough]], [[hemoptysis]]. when the disease progress, [[weight loss]], [[Failure to thrive]], and [[respiratory failure]] occurs in severe cases.
Symptoms of IPH in the acute phase may include the following:
:*Severe dyspnea
:*Cough
:*Hemoptysis
:*Worsening anemia
:*Rapid asphyxiation due to massive pulmonary hemorrhage
patients who present in the chronic phase of the disease may have:
:*Weight loss  
:*Failure to thrive  
:*Hypoxemic  respiratory failure in severe cases,


=== Physical Examination ===
=== Physical Examination ===
Physical examination findings vary depending on whether it is an acute or chronic presentation.
Common physical examination findings of [[IPH]] include [[tachypnea]], [[pallor]] during the acute phase, and [[hepatosplenomegaly]], [[failure to thrive]] and [[weight loss]], and signs of [[respiratory failure]] such as [[digital clubbing]] in the chronic phase in severe cases.
*In the acute phase, the physical examination may be completely normal or include respiratory signs such as tachypnea.
*In the chronic phase, there may be:
*Pallor
*Failure to thrive
*Weight loss
*Hepatosplenomegaly
*Digital clubbing and other signs of chronic hypoxia in the setting of pulmonary fibrosis


=== Laboratory Findings ===
=== Laboratory Findings ===
*Reduced hemoglobin counts and hematocrit, leucocytosis, and elevated erythrocyte sedimentation rate may be seen in patients with [[IPH]].
The laboratory findings consistent with [[IPH]] include reduced [[hemoglobin]] counts and [[hematocrit]], [[leucocytosis]], and elevated [[erythrocyte sedimentation rate]].


===Imaging Findings===
===Imaging Findings===
*Chest x-ray taken during an acute phase of IPH exacerbation may show diffuse alveolar infiltrates greatest at the lung bases.
A [[chest x-ray]] taken during an [[Acute (medical)|acute phase]] of [[IPH]] [[exacerbation]] may show [[diffuse]] [[alveolar]] infiltrates greatest at the [[Base of the lung|base of the lungs]]. Lungs CT scans may be helpful in the [[diagnosis]] of [[IPH]]. Findings on CT scan suggestive of [[IPH]] include ground-glass attenuation in the [[base of lung|base of lungs]] during the [[acute]] phase of [[IPH]].
*CT scans taken during an acute phase of IPH exacerbation may show ground-glass attenuation in the lung bases.  
[[Chromium]] and [[technetium]] based perfusion scans may be helpful in the [[diagnosis]] of [[IPH]]. Findings on these perfusion scans suggestive of IPH include: abnormal [[pulmonary]] [[uptake]] 12-24 hours after the [[injection]] in patients with [[pulmonary hemorrhage]].
*Chromium and technetium based perfusion scans show intra-alveolar bleeding. Scans with abnormal pulmonary uptake 12-24 hours after the injection have been observed in patients with pulmonary hemorrhage.


=== Other Diagnostic Studies ===
=== Other Diagnostic Studies ===
*Erythrocytes and hemosiderin-laden macrophages may be seen in sputum testing with hematoxylin-eosin and Prussian blue stains, indicating intra-alveolar bleeding. Stains and cultures for mycobacteria, bacteria, and fungus are done to rule out the infective cause.
Other diagnostic studies for [[IPH]] include [[sputum]] testing and [[bronchoalveolar lavage]] ([[BAL]]) for intact [[erythrocytes]] and hemosiderin-laden [[Macrophage|macrophages]], which demonstrate [[pulmonary hemorrhage]], and [[pulmonary function tests]], which generally shows a [[Restrictive Lung Disease|restrictive pattern]] of varying severity and decreased [[DLCO]].
*Alveolar macrophages filled with hemosiderin and intact erythrocytes and occasionally neutrophils in Bronchoalveolar lavage (BAL) has a higher diagnostic yield than sputum testing.
*Pulmonary function testing generally shows a restrictive pattern of varying severity. The carbon monoxide diffusing capacity (DLCO) can be elevated during the acute phase.


== Treatment ==
== Treatment ==
=== Medical Therapy ===
=== Medical Therapy ===
*There is no treatment for IPH; the mainstay of therapy is supportive care based on the presentation and acute vs. chronic nature of the patient.
There is no [[treatment]] for [[IPH]]; the mainstay of [[therapy]] is supportive care based on the [[presentation]] and [[acute]] vs. [[chronic]] nature of the patient. [[Immuno-suppressants]] in combination with [[steroids]] is used for severe cases. Supportive therapy for [[IPH]] includes [[blood transfusion]] to correct severe [[anemia]], and invasive [[ventilation]] support for [[respiratory failure]] secondary to [[alveolar]] [[hemorrhage]].
*Blood should be transfused to correct severe anemia and shock during the acute phase.
*Patients with acute IPH and respiratory failure secondary to alveolar hemorrhage may require invasive ventilation support. In these patients, it is also recommended to consider immunosuppressive therapy in addition to high dose systemic corticosteroids.
*Immuno-suppressants such as hydroxychloroquine, azathioprine, cyclophosphamide, and 6-mercaptopurine are sometimes used in combination with steroids for severe cases, or when steroids are contraindicated or not tolerated.
*Other treatment options with unknown efficacies include intravenous immunoglobulin (IVIG), plasmapheresis, liposteroids, and dietary modification (gluten-free diet in those with celiac disease and IPH has been shown to improve symptoms).


=== Surgery ===
=== Surgery ===
*Surgical intervention is not recommended for the management of [[IPH]].
Surgical intervention is not recommended for the management of [[IPH]].


==Prevention ==  
===Prevention===  
Preventative measures include maintenance doses of prednisone or prednisolone of 10 to 15 mg/kg/day. In general, if the patient does not have any recurrence in 18 to 24 months, further tapering and discontinuation of steroids can be attempted.<ref name="pmid32505591">{{cite journal |vauthors=Yang CT, Chiang BL, Wang LC |title=Aggressive corticosteroid treatment in childhood idiopathic pulmonary hemosiderosis with better outcome |journal=J. Formos. Med. Assoc. |volume= |issue= |pages= |date=June 2020 |pmid=32505591 |doi=10.1016/j.jfma.2020.05.022 |url=}}</ref>
Preventive measures for the [[secondary prevention]] of [[IPH]] include: [[maintenance dose|maintenance doses]] of [[prednisone]] or [[prednisolone]] of 10 to 15 mg/kg/day
===Future or investigational therapies===
More researches should be done in order to investigate the cause of [[idiopathic pulmonary hemosiderosis]] so that selective and directed [[therapeutic]] [[approaches]] can be undertaken.


==References==
==References==

Latest revision as of 05:52, 5 October 2020

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Editor-In-Chief: C. Michael Gibson, M.S., M.D. [1]Roghayeh Marandi

Overview

Idiopathic pulmonary hemosiderosis (IPH) is a rare disease of unknown etiology characterized by repeated episodes of a diffuse alveolar hemorrhage which cause periodic attack of tachycardia, pyrexia, pallor, fatigue, cyanosis, increasing dyspnea, signs of congestive cardiac failure, severe anamia and hemoptysis. The repeated alveolar hemorrhage causes the accumulation of hemosiderin, a by-product of hemoglobin breakdown, in the alveoli. Alveolar macrophages take up these hemosiderin molecules, usually within 36 - 72 hours, and can remain in the lungs for up to 8 weeks. Between attacks, patients may remain well but commonly there is chronic ill-health. Over the time, It can lead to multiple respiratory complications and permanent lung damage. It is not familial and is found primarily in children from a few months to 16 years of age and rarely be seen in adults.

Historical Perspective

IPH was first described as "brown lung induration" by Rudolf Virchow in 1864 in patients after their death. Wilhelm Ceelen gave a more detailed description of the condition after autopsies revealed large amounts of hemosiderin in 2 children in 1931. In 1944, the antemortem diagnosis was made by Waldenstrom.

Classification

Based on the duration of symptoms, pulmonary hemosiderosis may be classified as either acute or chronic phase.Pulmonary hemosiderosis may be classified into three groups based on disease characteristic: first group with circulating anti-glomerular basement membrane (anti-GBM) antibodies, second group, with immune complex disease, and the third group without known immunologic association or (Idiopathic pulmonary hemosiderosis).

Pathophysiology

After the repeated episodes of a diffuse alveolar hemorrhage, the alveolar macrophages are responsible for the repeated clean up of excess blood. As the macrophages degrade the erythrocytes, the excess iron from heme degradation within the alveolar macrophages stimulates intracellular ferritin molecules. Further processing of the ferritin leads to hemosiderin complexes.(see below for more information). In the early stages of pulmonary hemosiderosis, interstitial and intra-alveolar hemorrhage predominate, with collections of both free hemosiderin and hemosiderin-filled macrophages found in the alveolar spaces and the interstitium. When the disease progresses, interstitial fibrosis ensues. Pulmonary hemosiderosis can occur either as a primary lung disorder (Idiopathic pulmonary hemosiderosis) or as the sequela to other pulmonary, cardiovascular, or immune system disorder.

Causes

There are no established causes for idiopathic pulmonary hemosiderosis, but it is likely to be multifactorial. Some consider it to be an autoimmune condition. The evidence is backed by the fact that the disease responds to immunosuppressants. Other hypotheses for this condition include allergy, due to this frequent association with Cow's milk protein allergy, or genetic cause, due to the rare finding of familial clustering (but without any identified genes yet), and environmental factors such as its association with the fungi (Stachybotrys atra) exposure, or toxic insecticides (based on epidemiological studies in rural Greece), and premature birth.

Differentiating IPH from other Diseases

Idiopathic pulmonary hemosiderosis must be differentiated from other diseases that cause alveolar hemorrhage, such as those include infectious etiologies( ARDS, Streptococcus pneumonia, Staphylococcus aureus, and legionella, influenza A and Pneumocystis jirovecii), rheumatic diseases such as systemic lupus erythematosus, antiphospholipid antibody syndrome, Goodpasture disease, microscopic granulomatous polyangiitis, and mixed cryoglobulinemias, drug-induced injury in medications such as amiodarone, nitrofurantoin, and infliximab, Penicillamine, or from thromboembolic disease, bleeding disorders, and neoplasms.

Epidemiology and Demographics

The prevalence and incidence of idiopathic pulmonary hemosiderosis are relatively unknown because of the rare nature. IPH is more commonly observed among children. 20% of cases are adult-onset IPH.IPH affects males and females equally in childhood-onset IPH. Males are more commonly affected by IPH than females in adult-onset IPH.

Risk Factors

There are no established risk factors for Idipathic pulmonary hemosiderosis.

Natural History, Complications and Prognosis

The clinical spectrum of IPH ranges from asymptomatic cases to a chronic cough and dyspnea to repetitive hemoptysis with fatigue, anemia, and slowly progressive dyspnea and life-threatening acute respiratory failure. Common complications of IPH include Iron deficiency anemia and pulmonary fibrosis. Prognosis is generally variable, and the mean survival rate of patients with IPH is 2.5 to 5 years after diagnosis. Deaths can occur from acute massive hemorrhage or after progressive pulmonary insufficiency and right heart failure.

Diagnosis

There are no established criteria for the diagnosis of idiopathic pulmonary hemosiderosis. Lung biopsy is the gold standard for the diagnosis of IPH, where the hemosiderin-laden macrophages can be visualized. However, it is an invasive procedure and is often not practicable in children.

History and Symptoms

The most common symptoms of IPH in the acute phase include severe dyspnea, cough, hemoptysis. when the disease progress, weight loss, Failure to thrive, and respiratory failure occurs in severe cases.

Physical Examination

Common physical examination findings of IPH include tachypnea, pallor during the acute phase, and hepatosplenomegaly, failure to thrive and weight loss, and signs of respiratory failure such as digital clubbing in the chronic phase in severe cases.

Laboratory Findings

The laboratory findings consistent with IPH include reduced hemoglobin counts and hematocrit, leucocytosis, and elevated erythrocyte sedimentation rate.

Imaging Findings

A chest x-ray taken during an acute phase of IPH exacerbation may show diffuse alveolar infiltrates greatest at the base of the lungs. Lungs CT scans may be helpful in the diagnosis of IPH. Findings on CT scan suggestive of IPH include ground-glass attenuation in the base of lungs during the acute phase of IPH. Chromium and technetium based perfusion scans may be helpful in the diagnosis of IPH. Findings on these perfusion scans suggestive of IPH include: abnormal pulmonary uptake 12-24 hours after the injection in patients with pulmonary hemorrhage.

Other Diagnostic Studies

Other diagnostic studies for IPH include sputum testing and bronchoalveolar lavage (BAL) for intact erythrocytes and hemosiderin-laden macrophages, which demonstrate pulmonary hemorrhage, and pulmonary function tests, which generally shows a restrictive pattern of varying severity and decreased DLCO.

Treatment

Medical Therapy

There is no treatment for IPH; the mainstay of therapy is supportive care based on the presentation and acute vs. chronic nature of the patient. Immuno-suppressants in combination with steroids is used for severe cases. Supportive therapy for IPH includes blood transfusion to correct severe anemia, and invasive ventilation support for respiratory failure secondary to alveolar hemorrhage.

Surgery

Surgical intervention is not recommended for the management of IPH.

Prevention

Preventive measures for the secondary prevention of IPH include: maintenance doses of prednisone or prednisolone of 10 to 15 mg/kg/day

Future or investigational therapies

More researches should be done in order to investigate the cause of idiopathic pulmonary hemosiderosis so that selective and directed therapeutic approaches can be undertaken.

References

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