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出典(authority):フリー百科事典『ウィキペディア（Wikipedia）』「2013/04/30 13:12:36」(JST)

Total iron-binding capacity (TIBC) is a medical laboratory test that measures the blood's capacity to bind iron with transferrin.^[1] It is performed by drawing blood and measuring the maximum amount of iron that it can carry, which indirectly measures transferrin^[2] since transferrin is the most dynamic carrier. TIBC is less expensive than a direct measurement of transferrin.^[3]^[4]

The TIBC should not be confused with the UIBC, or "unsaturated iron binding capacity" (22753-8 and 35216-1). The UIBC is calculated by subtracting the serum iron from the TIBC. ^[5]

Interpretation

Taken together with serum iron and percent transferrin saturation clinicians usually perform this test when they are concerned about anemia, iron deficiency or iron deficiency anemia. However, because the liver produces transferrin, alterations in function (such as cirrhosis, hepatitis, or liver failure) must be considered when performing this test. It can also be an indirect test of liver function, but is rarely used for this purpose.

The percent transferrin saturation (i.e., the result of the formula of serum iron/TIBC x 100) can also be a useful indicator.

Condition	Serum iron	Transferrin and TIBC	Percent transferrin saturation
iron deficiency anemia	Low	High. The liver produces more transferrin, presumably attempting to maximize use of the little iron that is available.	Low, as there is insufficient iron.
anemia of chronic disease	Low, as the body holds iron intracellularly with ferritin.	Low. The body produces less transferrin (but more ferritin), presumably to keep iron away from pathogens that require it for their metabolism. This is mainly regulated by increased hepcidin production.	Normal
pregnancy or use of hormonal contraception, but without iron deficiency	Normal	High. The liver increases the production of transferrin, thus raising TIBC.	Low, as there is excess transferrin with normal serum iron levels.

These examples demonstrate that to properly understand a value for TIBC, one also must know the serum iron, the percent transferrin saturation, and the individual clinical situation.

Usual values

Reference ranges for blood tests, comparing blood content of iron and related compounds (shown in brown and orange) with other constituents.

Normal reference ranges are:

Serum iron: Male 65–177 μg/dL (11.6–31.7 μmol/L); Female 50–170 μg/dL (9.0–30.4 μmol/L)
TIBC: 250–370 μg/dL (45-66 μmol/L)^[6]
Transferrin saturation: Male 20–50%; Female 15–50%
Serum ferritin: Male 20-250 μg/L, Female 15-150 μg/L^[6]

μg/dL = micrograms per deciliter; μmol/L = micromoles per litre.

Laboratories often use different units and "normal" may vary by population and the lab techniques used. Look at the individual laboratory reference values to interpret a specific test (for instance, your own).

References

^ "MedlinePlus Medical Encyclopedia: Total iron binding capacity". Retrieved 2008-12-31.
^ Yamanishi H, Iyama S, Yamaguchi Y, Kanakura Y, Iwatani Y (January 2003). "Total iron-binding capacity calculated from serum transferrin concentration or serum iron concentration and unsaturated iron-binding capacity". Clin. Chem. 49 (1): 175–8. doi:10.1373/49.1.175. PMID 12507977.
^ Kasvosve I, Delanghe J (October 2002). "Total iron binding capacity and transferrin concentration in the assessment of iron status". Clin. Chem. Lab. Med. 40 (10): 1014–8. doi:10.1515/CCLM.2002.176. PMID 12476940.
^ Gambino R, Desvarieux E, Orth M, et al. (December 1997). "The relation between chemically measured total iron-binding capacity concentrations and immunologically measured transferrin concentrations in human serum". Clin. Chem. 43 (12): 2408–12. PMID 9439462.
^ "Iron Transport". Retrieved 2008-12-31.
^ ^a ^b Harrison's Principles of Internal Medicine. 17th Edition (2008). Pg. 2432 (Table 351-2)

UpToDate Contents

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1. 成人における鉄欠乏性貧血の原因および診断 causes and diagnosis of iron deficiency anemia in the adult
2. 鉄のバランス調節 regulation of iron balance
3. 慢性疾患の貧血（［慢性］炎症時の貧血） anemia of chronic disease anemia of chronic inflammation
4. 小児におけるむずむず脚（レストレスレッグス）症候群と周期性四肢運動障害 restless legs syndrome and periodic limb movement disorder in children
5. 乳幼児における鉄欠乏：スクリーニング、予防、臨床症状、および診断 iron deficiency in infants and young children screening prevention clinical manifestations and diagnosis

English Journal

Serum prohepcidin and other iron metabolism parameters in elderly patients with anemia of chronic disease and with iron deficiency anemia.

Przybyszewska J, Zekanowska E, Kędziora-Kornatowska K, Boinska J, Cichon R, Porzych K.AbstractINTRODUCTION The diagnosis of iron deficiency anemia in the context of the anemia of chronic disease in the elderly is often difficult due to the existence of many disorders. Recent studies show that the indication of hepcidin (in conjunction with existing diagnostic methods) can probably help in the differential diagnosis of iron deficiency anemia and anemia of chronic disease. OBJECTIVES The aim of this study was to evaluate the differential diagnostic value of serum prohepcidin in elderly patients with iron deficiency anemia(IDA) and anemia of chronic disease (ACD). PATIENTS AND METHODS Sixty-five persons were included in this study: 26 patients with anemia of chronic diseases (ACD), 13 patients with iron deficiency anemia (IDA), and 26 age-matched controls. Prohepcidin, ferritin, soluble transferrin receptor, erythropoietin and interleukin-6 were measured using commercially available ELISA kits. Iron, TIBC, transferrin, C-reactive protein and complete blood count were assayed using standard laboratory methods. RESULTS Prohepcidin concentrations were similar in ACD patients (196.59 ng/ml) in comparison with IDA patients (230.16 ng/ml) (p=0.3456). The group of ACD patients revealed significantly lower levels of TIBC in comparison with the IDA patients (p<0.0001). Serum ferritin concentration in ACD patients was almost 20-fold higher in comparison with IDA patients (p<0.0001). CRP and IL-6 concentrations in ACD patients were significantly higher in comparison with IDA patients. CONCLUSIONS Results of this study indicate that serum prohepcidin has limited differential diagnostic value / does not distinguish IDA and ACD in elderly patients.
Polskie Archiwum Medycyny Wewnetrznej.Pol Arch Med Wewn.2013 Jan 8. pii: AOP_13_003. [Epub ahead of print]
INTRODUCTION The diagnosis of iron deficiency anemia in the context of the anemia of chronic disease in the elderly is often difficult due to the existence of many disorders. Recent studies show that the indication of hepcidin (in conjunction with existing diagnostic methods) can probably help in th
PMID 23299925

Serum iron profile and ELISA-based detection of antibodies against the iron-regulated protein HupB of Mycobacterium tuberculosis in TB patients and household contacts in Hyderabad (Andhra Pradesh), India.

Sivakolundu S, Mannela UD, Jain S, Srikantam A, Peri S, Pandey SD, Sritharan M.SourceDepartment of Animal Sciences, School of Life Sciences, University of Hyderabad, Prof. C.R. Rao Road, Gachibowli, Hyderabad 500 046, India.
Transactions of the Royal Society of Tropical Medicine and Hygiene.Trans R Soc Trop Med Hyg.2013 Jan;107(1):43-50. doi: 10.1093/trstmh/trs005. Epub 2012 Oct 19.
BACKGROUND: HupB is a 28 kDa cell-wall-associated protein co-expressed with the siderophores mycobactin and carboxymycobactin in iron-limited Mycobacterium tuberculosis. HupB is expressed in vivo and anti-HupB antibodies are present in the serum of TB patients.METHODS: The aims of this study were to
PMID 23222944

Japanese Journal

血液透析患者の鉄代謝指標の日内変動

水口隆,岡田和美,水口潤,川島周
日本透析医学会雑誌 = Journal of Japanese Society for Dialysis Therapy 43(6), 493-499, 2010-06-28
… 血液透析（HD）患者における鉄代謝指標の日内変動を観察した．HD患者の血清鉄（sFe）値は19時54±29 μg/dLに比して10時74±35 μg/dLと有意（p＝0.0064）に10時が高値であった．総鉄結合能（TIBC）と血清フェリチン（sFtn）値は19時と10時で有意差はなかった．トランスフェリン鉄飽和率（TSAT）は19時22.6±11.9％に比して10時30.8±15.7％と有意（p＝0.0060）に10時が高値であった．sFe値とTSATには午前中が夕方に比して高値を示す日内変動 …
NAID 10026912631

金属鉄,総鉄結合能(TIBC),不飽和鉄結合能(UIBC) (広範囲血液・尿化学検査免疫学的検査(第7版・2)その数値をどう読むか) -- (生化学的検査(2))

伊藤薫樹,石田陽治
日本臨床 68(-) (970), 301-304, 2010-01
NAID 40016932841

Related Pictures

★リンクテーブル★

国試過去問	「112F036」「108I010」
リンク元	「サラセミア」「血清鉄」「トランスフェリン」「不飽和鉄結合能」「総鉄結合能」
関連記事	「TI」

「112F036」

Total iron-binding capacity
	Diagnostics
	; transferrin
MedlinePlus	003489
LOINC	14800-7, 35215-3, 2501-5

　　[★]

鉄欠乏性貧血と慢性疾患に伴う貧血との鑑別に有用なのはどれか。2つ選べ。

[正答]

※国試ナビ4※　［112F035］←［国試_112］→［112F037］

「108I010」

　　[★]

慢性炎症性疾患に伴う貧血で誤っているのはどれか。

a　Fe値低下
b　赤血球寿命短縮
c　フェリチン値低下
d　ヘプシジン産生亢進
e　総鉄結合能〈TIBC〉低下

[正答]

※国試ナビ4※　［108I009］←［国試_108］→［108I011］

「サラセミア」

　　[★]

英: thalassemia
同: 地中海性貧血 Mediterranean貧血症 Mediterranean anemia、サラセミア症候群 thalassemia syndrome
関: 重症型サラセミア、軽症型サラセミア、クーリー貧血

概念

ヘモグロビンの量的な異常による。
ヘモグロビンを構成するグロビン鎖の合成障害により特定のグロビン鎖の合成が抑制されて発症する先天性溶血性貧血

疫学

参考1

九州大などの地域限定の新生児臍帯血スクリーニング調査報告によればサラセミアの発症頻度は0.1%
九州や西日本に多い。

IMD

地中海沿岸地域、アフリカ全土、東南アジアなどに多い。
日本ではβサラセミアは1,000人に1人の頻度、αサラセミアはそれより頻度が低い。

病型

病因による分類

αサラセミア：α鎖グロビンの産生低下：HbBart's(γ鎖4量体)、HbH((β鎖4量体)
βサラセミア：β鎖グロビンの産生低下：HbA2(α鎖2量体/γ鎖2量体)、HbF((α鎖2量体/δ鎖2量体)
δβサラセミア：
ヘモグロビン構造変異型

遺伝子型による分類

ホモ接合型、ヘテロ接合型

臨床症状による分類

βサラセミア

重症型 thalassemia major: 輸血依存
中等症型 thalassemia intermedia: 中等度
軽症型 thalassemia minor: 無症候、キャリアー

病態

産生抑制されたグロビン鎖の代わりに、抑制されていないグロビン鎖が過剰に産生され、赤血球・赤芽球内に変性沈殿。これらが網内系で破壊される　→　溶血
代償的な赤血球の産生が増加、および骨髄内での無効造血の増加によりさらに骨髄での赤血球産生が高まり骨変形を来す。

症候

貧血：皮膚・粘膜が蒼白。
溶血・無効造血：黄疸、肝脾腫、骨変化(サラセミア顔貌)、病的骨折、精神および身体の発育障害。
二次的変化：Fe過剰による皮膚色素沈着、感染症による下腿潰瘍、扁桃炎、胆道感染など。

検査

末梢血塗沫

標的赤血球

血算

小球性低色素性貧血

血液生化学

血清鉄：上昇
TIBC：→/軽度↓
フェリチン：上昇　　　←　　　無効造血による。　無効造血でなぜ上昇？

鉄代謝

血漿鉄交代率 PIT：低下
PIDT1/2：低下　　←　鉄の代謝回転が早い。投与した59Feは赤芽球に取り込まれても、無構造血により再び末梢に出現するため、血清からの消失速度が低下する？
%RCU：低下　←　赤血球鉄利用率のことで、投与した59Feが赤血球中にヘム鉄として取り込まれるかどうかをみる。無構造血により骨髄などに59Feが分散して%RCUが低下する。