Poster presentation prepared with medical students, Sarah Goaslind, and Matthew Koller.
Presentation of an individual with acute onset weakness of upper and lower extremities. Found to have significant hypokalemia and hyperthyroidism. The discussion emphasized the importance of assessment of thyroid function in individuals presenting with hypokalemic paralysis as well as possible mutations in potassium channels that increase susceptibility to thyrotoxic periodic paralysis.
Circulatory Shock, types and stages, compensatory mechanisms
Hypokalemic and Thyrotoxic Periodic Paralysis
1. Thyrotoxic Periodic Paralysis
with Associated Hypokalemia
DISCUSSION
• Thyrotoxicperiodicparalysis(TPP) isa raredisorder
causingpainlessmuscleweakness.
• Thyroxinestimulates theNa⁺/K⁺pumps, causingK+
to shiftintracellularly.Genemutationsinpotassium
channel Kir2.6 havebeen found to playa role.1,2
• TPP is broughton by exercise,fasting,or
carbohydrate-rich meals and is associated with Asian
males over 20 y/o. 2
• Our Asian patientturned 20 yearsoldtheday he
presented to the ED. Followingdiagnosisof TPP,he
was treated with potassiumreplacementand
counseled to avoid intensesportsandeatlessblack
licorice. On Day 3,hewas discharged on
methimazolewith closeEndocrinology follow-up.
CASE PRESENTATION
A 20 y/o Asian malewithno pastmedical history
presented to the ED with acuteonsetweaknessin his
upper and lower extremities. Herecentlybegan
a strenuousexerciseprogramandreported a similar
episode3 yearsago,which resolved in a fewhours.
SH: Exchangestudent.Arrived in theU.S.one month
ago and liveswith roommates.Denies substanceuse.
Consumes "a good amount"of black licorice.
FH: Noncontributory
Vitalswereunremarkable.
Examshowed
• 3/5 strength BUE;2/5 BLE; weak plantarflexion;no
dorsiflexion
• No thyromegaly appreciated
CONCLUSION
In individualspresentingwith hypokalemicparalysis,
itis importantto considerhyperthyroid stateto
avoid delay indiagnosisand treatmentof TPP and to
help differentiatefromother causes of hypokalemia
and paralysis.
REFERENCES
1. He L, Lawrence V, Moore WV, Yan Y. Thyrotoxic periodic paralysis in an adolescent male: A case report and literature review. Clinical Case Reports. 2020;9(1):465-469.
doi:10.1002/ccr3.3558
2. Meseeha M, Parsamehr B, Kissell K, Attia M. Thyrotoxic periodic paralysis: a case study and review of the literature. J Community Hosp Intern Med Perspect. 2017 Jun
6;7(2):103-106. doi: 10.1080/20009666.2017.1316906. PMID: 28638574; PMCID: PMC5473192.
3. Vijayakumar A, Ashwath G, Thimmappa D. Thyrotoxic periodic paralysis: clinical challenges. J Thyroid Res. 2014;2014:649502. doi: 10.1155/2014/649502. Epub 2014 Feb 20.
PMID: 24695373; PMCID: PMC3945080.
4. Siddamreddy S, Dandu VH. Thyrotoxic Periodic Paralysis. 2020 Jul 26. In: StatPearls [Internet]. Treasure Island (FL): StatPearls Publishing; 2020 Jan–. PMID: 32809505.
5. Ryan DP, Dias da Silva MR, Soong TW, et al. Mutations in Potassium Channel Kir2.6 Cause Susceptibility to Thyrotoxic Hypokalemic Periodic Paralysis. Cell.2010;140(1):88-
98. doi:10.1016/j.cell.2009.12.024
Sarah Goaslind, OMS-III; Matthew Koller, OMS-III; Matthew Fabiszak, DO
K 1.4 Mg 1.7 CK 14,072
TSH <0.01 T3 253 T4 2.30
• Underlyinghyperthyroidismisoften subtle,
which causes difficulty inearlydiagnosis.3
• Oncea euthyroidstateisachieved,TPP is
curable.1,2
• Hyperthyroidismhasa higher incidencein
females,butgreater than 95%of TPP occursin
males.2
• "Reported incidences varyfrom1.9%
in Japanesethyrotoxicpatientsto 1.8%in
Chinesethyrotoxicpatients."4
HPI
Histories
Diagnostic
Data
Phys.
Exam
Figure 2 – Outlining howmutations in potassium
channelKir2.6 cause susceptibilityto TPP 5
Figure 1 – EKG showingpatient's prolongedQT andU waves
![Thyrotoxic Periodic Paralysis
with Associated Hypokalemia
DISCUSSION
• Thyrotoxicperiodicparalysis(TPP) isa raredisorder
causingpainlessmuscleweakness.
• Thyroxinestimulates theNa⁺/K⁺pumps, causingK+
to shiftintracellularly.Genemutationsinpotassium
channel Kir2.6 havebeen found to playa role.1,2
• TPP is broughton by exercise,fasting,or
carbohydrate-rich meals and is associated with Asian
males over 20 y/o. 2
• Our Asian patientturned 20 yearsoldtheday he
presented to the ED. Followingdiagnosisof TPP,he
was treated with potassiumreplacementand
counseled to avoid intensesportsandeatlessblack
licorice. On Day 3,hewas discharged on
methimazolewith closeEndocrinology follow-up.
CASE PRESENTATION
A 20 y/o Asian malewithno pastmedical history
presented to the ED with acuteonsetweaknessin his
upper and lower extremities. Herecentlybegan
a strenuousexerciseprogramandreported a similar
episode3 yearsago,which resolved in a fewhours.
SH: Exchangestudent.Arrived in theU.S.one month
ago and liveswith roommates.Denies substanceuse.
Consumes "a good amount"of black licorice.
FH: Noncontributory
Vitalswereunremarkable.
Examshowed
• 3/5 strength BUE;2/5 BLE; weak plantarflexion;no
dorsiflexion
• No thyromegaly appreciated
CONCLUSION
In individualspresentingwith hypokalemicparalysis,
itis importantto considerhyperthyroid stateto
avoid delay indiagnosisand treatmentof TPP and to
help differentiatefromother causes of hypokalemia
and paralysis.
REFERENCES
1. He L, Lawrence V, Moore WV, Yan Y. Thyrotoxic periodic paralysis in an adolescent male: A case report and literature review. Clinical Case Reports. 2020;9(1):465-469.
doi:10.1002/ccr3.3558
2. Meseeha M, Parsamehr B, Kissell K, Attia M. Thyrotoxic periodic paralysis: a case study and review of the literature. J Community Hosp Intern Med Perspect. 2017 Jun
6;7(2):103-106. doi: 10.1080/20009666.2017.1316906. PMID: 28638574; PMCID: PMC5473192.
3. Vijayakumar A, Ashwath G, Thimmappa D. Thyrotoxic periodic paralysis: clinical challenges. J Thyroid Res. 2014;2014:649502. doi: 10.1155/2014/649502. Epub 2014 Feb 20.
PMID: 24695373; PMCID: PMC3945080.
4. Siddamreddy S, Dandu VH. Thyrotoxic Periodic Paralysis. 2020 Jul 26. In: StatPearls [Internet]. Treasure Island (FL): StatPearls Publishing; 2020 Jan–. PMID: 32809505.
5. Ryan DP, Dias da Silva MR, Soong TW, et al. Mutations in Potassium Channel Kir2.6 Cause Susceptibility to Thyrotoxic Hypokalemic Periodic Paralysis. Cell.2010;140(1):88-
98. doi:10.1016/j.cell.2009.12.024
Sarah Goaslind, OMS-III; Matthew Koller, OMS-III; Matthew Fabiszak, DO
K 1.4 Mg 1.7 CK 14,072
TSH <0.01 T3 253 T4 2.30
• Underlyinghyperthyroidismisoften subtle,
which causes difficulty inearlydiagnosis.3
• Oncea euthyroidstateisachieved,TPP is
curable.1,2
• Hyperthyroidismhasa higher incidencein
females,butgreater than 95%of TPP occursin
males.2
• "Reported incidences varyfrom1.9%
in Japanesethyrotoxicpatientsto 1.8%in
Chinesethyrotoxicpatients."4
HPI
Histories
Diagnostic
Data
Phys.
Exam
Figure 2 – Outlining howmutations in potassium
channelKir2.6 cause susceptibilityto TPP 5
Figure 1 – EKG showingpatient's prolongedQT andU waves](https://image.slidesharecdn.com/hypokalemicperiodicparalysis2-210310170220/85/Hypokalemic-and-Thyrotoxic-Periodic-Paralysis-1-320.jpg)
